Threads Text Attachment Counter

Use this free counter to check your Threads text attachment against the 10,000-character limit. Paste your draft in the tool above and get a live character count, a word count, a reading-time estimate, a unique-link tally against the 5-link cap, and a format advisor that tells you whether your content fits the attachment, the post, or a thread chain. No login required, no subscription, works on every device.

What Is the Threads Text Attachment?

The Threads text attachment is the platform’s long-form writing field. It gives every account 10,000 characters of formatted text that attaches to a post or a reply, free of charge, no subscription needed. Meta launched it on September 4, 2025, with an unusually clear explanation of the problem it solves.

Why did it exist at all? Before September 2025, Threads users who wanted to share anything longer than 500 characters had two options: take a screenshot of their document or split the content across a chain of connected posts. Screenshots are inaccessible, unsearchable, and impossible to copy. Thread chains are fragmented and hard to read as a single piece. The text attachment replaces both workarounds with a native, readable format that expands directly inside the Threads feed.

The best way to understand the feature is as a two-field writing system. You get 500 characters for the post that carries the hook — the sentence or two that appears in the feed and earns a tap — and 10,000 characters for the attachment that carries the substance — the essay, guide, excerpt, or analysis that rewards the tap. Those two budgets are completely independent. A post can use all 500 of its characters while its attachment uses all 10,000 of its own. This counter is built around that two-field workflow.

How the Attachment Appears in the Feed

When a post carries a text attachment, the attachment appears as a gray block below the main post text. The opening lines of the attachment are visible in the feed as a preview. A reader who wants the full text taps “Read more” and the block expands in place — no redirect, no new tab, no leaving Threads. The full formatted text is readable inside the thread.

One detail most guides miss: if you include a link in your main post, that link also appears inside the expanded attachment. The attachment effectively doubles as a link-preview surface. Meta’s own announcement leans into this explicitly — if you are sharing content hosted elsewhere, the recommended pattern is to put the link in the body of the main post and let it echo inside the attachment automatically.

How the Attachment Renders Compared to X Articles and LinkedIn Articles

The Verge called the attachment “a Threads-y take on X’s Articles feature” at launch, and PCMag’s headline captured the key nuance: Threads now lets you post 10,000 characters, but not in a way you would expect. It is not a longer post. It is a separate, formatted document that attaches to a post. LinkedIn Articles works similarly in structure — a separate long-form field — but LinkedIn’s article limit runs to about 110,000 characters with full heading tags and embedded images. The Threads attachment is plaintext with styling, no embedded media. For writers choosing where long-form content lives, that distinction matters.

The 10,000-Character Limit: What Counts, What Does Not

Meta’s API documentation defines the text attachment as a single plaintext field with a maximum of 10,000 characters. Everything visible in the text counts toward that number. Here is the complete picture.

What Counts Toward the 10,000

• Letters, digits, and punctuation — one character each.
• Spaces — one character each.
• Line breaks — one character each.
• Hashtags and @mentions — counted character by character.
• URLs at their full literal length — a 60-character URL costs 60 characters (no shortening, no t.co equivalent).
• Emojis — counted as the number of UTF-8 bytes, per Meta's API documentation: a standard emoji costs 4 characters. Flags and skin-tone modifiers cost 8, a three-person family sequence costs 18, and a four-person family costs 25.
• CJK characters (Chinese, Japanese, Korean) — 1 character each, the same multilingual treatment as the main post.

What Does Not Count Toward the 10,000

• The 500-character main post field — a completely separate budget.
• The optional link_attachment_url field — a separate API parameter, not part of the plaintext count.
• Formatting (bold, italic, underline, strikethrough, highlight) — stored as a separate styling payload with zero character cost. More on this in the formatting section.

How Much Writing Is 10,000 Characters?

At a standard English word length of roughly 5 characters including spaces, 10,000 characters is approximately 1,500 to 2,000 words — a short newsletter section or a feature-length blog post. At a 238-words-per-minute silent reading pace, that is six to seven minutes of reading. At a comfortable speaking pace of 130 words per minute, it is about eleven to twelve minutes of audio.

Most attachments should not aim for the ceiling. A focused 1,500 to 3,000 characters that ends with a clear call to action usually out-performs a near-10,000-character wall of text, because the tap-to-expand is a commitment you are asking the reader to make. The format advisor in the tool above runs this arithmetic live as you type.

Emoji Weights: The Documented Rule Most Counters Miss

Ask ten character counters how an emoji is counted and you will get two answers. The answer that matters comes from Meta itself: the Threads API documentation states, in its specification of the post text field, that "for the post character limit, emojis are counted as the number of UTF-8 bytes." A standard emoji is 4 bytes, so it costs 4 characters — not 2, and certainly not 1. A flag or a skin-tone modifier costs 8, a three-person family sequence costs 18, and a four-person family costs 25.

Almost every counter on the web still misses this. Most one-page counters simply use JavaScript's .length, which counts a standard emoji as 2 (UTF-16 code units), and community guides repeat the 2-character figure — a few even report 1. Some scheduling platforms validate Threads text in UTF-16 as well. Against the documented rule, all of those under-count emoji-heavy drafts, which is the dangerous direction: a draft that clears a UTF-16 counter can still be rejected at publish.

Meta does not publish a separate counting rule for the attachment's own plaintext field. This counter closes that gap the safe way: it applies the documented UTF-8 rule to every field, attachment included. The result is the strictest documented counting on the platform — if your draft fits here, it fits everywhere. On an emoji-light draft the difference is invisible; on an emoji-heavy one, this is the counter that will not let you down.

Five Formatting Styles, Zero Character Cost

The text attachment editor supports formatting by text selection, not by markdown syntax. There is no asterisk to type, no underscore to place. You select text in the editor and apply the style. Here are the five styles available:

Why Formatting Never Changes Your Character Count

This is the most useful technical fact about text attachments and the one most guides fail to explain. Meta models a text attachment as two separate objects: a plaintext field (what the 10,000-character limit measures) and a styling payload — text_with_styling_info, an array of offset, length, and style flags. The styling payload records where each formatted range starts, how long it is, and which styles apply. It is completely separate from the counted text.

The practical consequence: bold an entire paragraph, italicize every third word, highlight the opening sentence in an API post — the character count does not move by a single character. What this counter reports is what the app will count, whether you format afterward or not.

One API constraint to note: styling ranges within the text_with_styling_info array must not overlap. Two styles can apply to the same range by including both in a single range’s styling_info array (for example "styling_info": ["bold","italic"]), but two separate range objects that cover the same character positions will be rejected.

How to Use Formatting for Structure

Formatting is the attachment’s structural toolkit, since the attachment has no heading tags:

• Bold lines — use them as headings. One bolded line per section gives a 5,000-character piece a scannable skeleton.
• Italic — emphasis and asides. Also correct for titles of books, films, or articles.
• Strikethrough — visible corrections and updates. “The event is on ~~Friday~~ Sunday” is clear and honest.
• Underline — use sparingly; readers associate underline with links and it creates confusion if overused.

The Five-Link Rule: How Links Are Counted and What Happens When You Exceed It

Links are where the text attachment has documented mechanics that almost no creator-facing guide explains. Here is the complete rule from Meta’s official API documentation:

How the Count Works: Official Examples from Meta’s API Documentation

Meta’s own documentation gives three examples that make the dedup logic concrete:

What Happens When You Exceed 5 Links

Since December 22, 2025, posts with more than 5 unique links fail to publish at the media container creation step. The API returns the error code THREADS_API__LINK_LIMIT_EXCEEDED. The post is not published. No partial publish happens. The fix is to reduce the total unique URL count across the post text and attachment text to 5 or fewer before retrying.

For most writers, the practical rule is simple: one link in the main post, keep the attachment link-light. The link in the main post also renders inside the expanded attachment automatically — you get the preview card in the post and the echo in the attachment without spending two of your five links.

The link_attachment_url vs link_attachment Distinction (Important for API Developers)

In the main post API, the field for attaching a link preview is called link_attachment. Inside the text_attachment object, the equivalent field is called link_attachment_url. These are different parameters in different objects. Confusing them produces silent failures or the wrong link displaying. If you are building an integration that publishes text attachments, the correct structure is the text_attachment JSON object with plaintext (required), link_attachment_url (optional), and text_with_styling_info (optional).

Five Rules Before You Post: A Plain-English Checklist

Meta’s API documentation lists five hard constraints for text attachments. Most creator-facing guides never mention them. A post that violates any of these fails silently in the app or returns an API error — with no clear message about why. Know them before you publish:

• Your main post is text-only. No photos, videos, GIFs, carousels, or other media — text attachments can only be attached to text-only posts.
• Your main post does not contain a poll. Text attachments and polls are incompatible.
• You are not doubling up link attachments. A link_attachment_url cannot be added to the text attachment if the main post already carries a link attachment (the preview card) — only one link attachment is allowed across the post unit.
• Your total unique link count is 5 or fewer across the post text, attachment text, and the link_attachment_url field combined.
• Your attachment plaintext is 10,000 characters or fewer.

Can a Reply Carry a Text Attachment?

Yes. Meta’s developer documentation explicitly confirms that text attachments work “in a post or a reply” with up to 10,000 characters. A reply has the same attachment capabilities as a standalone post — the same character limit, the same formatting options, the same link rules, the same carrier restrictions (text-only, no poll).

This opens a use case that most guides ignore completely: long-form Q&A threads. If someone asks a detailed question in a Threads post, your reply can carry a full 10,000-character answer as an attachment — a structured guide, a step-by-step tutorial, a detailed analysis — all expanding directly inside the original thread. Each reply with an attachment collects its own likes and further replies, making the discussion self-contained and deep.

Use the Reply mode in the counter above when drafting a long reply. The counting rules are identical to the Attachment mode, with the feed-fold marker active for the 500-character reply field above it.

Text Attachment or Thread Chain? How to Choose

Every long piece of content on Threads ships in one of two shapes: a text attachment on a single post, or a chain of 500-character posts threaded together. The format advisor in the counter above does this arithmetic live. Here is the framework:

The Auto-Split Trap (May 2026 Change)

In May 2026, the Threads mobile app formalized a behavior that catches many writers off guard: pasting more than 500 characters into the main post composer automatically splits the content into a multi-post thread. The app chooses the break points. For carefully structured long-form content, those break points are almost always wrong.

The correct workflow is to draft your attachment content in this counter first, in Attachment mode, with the 10,000-character budget visible. When the count is confirmed, paste it into the attachment editor inside the app — not into the main post field. If you accidentally paste into the main post field, the auto-split fires and your formatting structure is gone. That is exactly the failure this tool’s format advisor is designed to prevent.

Threads Text Attachment vs X Premium: The Free vs Paid Long-Form Comparison

The text attachment is the sharpest free-versus-paid contrast between any two major social platforms. Here is the complete picture:

The key comparison: X locks long-form posts of up to 25,000 characters behind its paid tiers and reserves its Articles feature for the top tier. Threads gives 10,000 formatted characters to every free account. For a writer, journalist, or creator who would consider paying for X primarily for the long-form posting capability, the Threads text attachment delivers equivalent utility at zero cost.

Where X Premium wins is raw length — 25,000 characters versus 10,000 — and the fact that each long post appears as a full post in the feed rather than a tap-to-expand block. Where Threads wins is access: no payment required, no tier to unlock, no credit card needed. For the majority of long-form use cases — an essay, a newsletter tease, a chapter excerpt, a think piece — 10,000 characters is more than enough.

The 15-Minute Edit Window: Why Pre-Publish Accuracy Is Non-Negotiable

Threads posts can be edited for 15 minutes after publishing. Within that window, you can change the text of the post. What you cannot do: add an attachment that was not there at publish, or swap an attachment for a different one. Additional attachments cannot be added during an edit.

For a 3,000-character text attachment, a typo found at minute 16 presents an unpleasant choice: delete the post and repost it (losing all engagement it has already received) or live with the error. Neither option is good. The professional habit is to treat publishing as final. Draft the attachment in this counter, verify the count and link tally, read it once more, and only paste it into the app when it is actually ready.

The Fediverse Delay: A Detail No Other Guide Mentions

Threads is integrating with the fediverse — the decentralized network of servers running on the ActivityPub protocol (the same system that powers Mastodon). Users who opt in to fediverse sharing have their posts visible on Mastodon and other ActivityPub-compatible platforms. There is a timing detail that matters for writers with cross-platform audiences: posts are shared to the fediverse only after the 15-minute edit window closes. The delay exists specifically so your edits can land before the post leaves Threads.

That means an edit inside the window is not free of consequences: the fediverse copy — the edited version — still waits until the window closes. For writers whose Threads audience overlaps with Mastodon, timing matters: publish once, publish final, and let the edit window close before expecting the post to appear in the fediverse feed.

Publishing Text Attachments Through the Threads API

Text attachments are fully supported by the Threads API — support was added on October 3, 2025, a month after the feature launched, and the documentation was last updated July 2, 2026. This matters even if you never write code, because it is how scheduling tools and publishing pipelines create attachments. Understanding the API structure also tells you exactly what data the attachment carries and retrieves.

The Two-Step Publish Flow

Step 1 — create a media container:

POST /{threads-user-id}/threads

Include the text_attachment JSON object with these fields:

• plaintext (required) — the attachment text, maximum 10,000 characters
• link_attachment_url (optional) — a URL to attach to the attachment
• text_with_styling_info (optional) — array of offset, length, and styling_info objects defining formatted ranges; ranges must not overlap

Step 2 — publish the container:

POST /{threads-user-id}/threads_publish

Pass the media container ID returned in Step 1. The post with its attachment publishes as one unit.

Retrieving Text Attachments

To retrieve a post with its attachment, request the text_attachment field from the GET endpoint. The response returns the plaintext, the link_attachment_url, and the text_with_styling_info ranges — the complete reconstruction of the formatted document. This is how archival tools, analytics platforms, and scheduling tools read back content they have published.

API Rate Limits

API publishing inherits the platform’s standard rate limits: 250 posts and 1,000 replies per rolling 24-hour window per profile. A heavy attachment publishing schedule fits comfortably inside the daily quota. The five-link rule, the text-only restriction, and the 10,000-character limit all apply identically through the API and the in-app editor.

Scheduling Tool Compatibility: A Critical Note

Not all third-party scheduling tools pass the text_attachment object through their Threads integration. Some tools support the 500-character main post field only and silently strip the attachment when publishing. Before building a workflow around scheduled text attachments, verify in your scheduling tool’s documentation that it explicitly supports the text_attachment API parameter — not just Threads scheduling in general. A scheduler that “supports Threads” is not the same thing as a scheduler that supports Threads text attachments.

A Writer’s Playbook for Attachments That Get Read

An attachment is a promise of depth. The 500-character post above it is the pitch that sells the promise. Every element of the writing strategy flows from one fact: the feed shows your post text, not the attachment’s opening line. The post carries the entire burden of earning the tap.

Writing the Hook: Where Most Attachment Posts Fail

The 500-character main post is not an opportunity to cram in as many words as possible before the tap. It is an opportunity to write the single best question, provocation, or teaser that makes a reader want to see what is behind the “Read more.” A 70-character hook with a genuine curiosity gap will out-earn a 480-character summary almost every time.

A practical engagement guide for the main post field:

• Under 150 characters: strongest hook signal. One question, one claim, one sharp contrast. The entire hook is visible without truncation on every feed width.
• 150 to 350 characters: standard hook territory. Enough space for context plus a payoff tease. Works well for journalists and educators who need to establish credibility before asking for the tap.
• 350 to 500 characters: summary territory. You are essentially writing an abstract of the attachment. Useful for documentation and formal announcements where readers need the overview before they commit to the depth.

The feed-fold marker in this tool’s Post mode shows approximately where the feed truncates the main post behind a “more” tap — around the 175-character mark. Front-load your most compelling element before that line. Everything after it is asking the reader to perform two taps: one to expand the post, one to open the attachment.

The Tease-and-Redirect Pattern: Meta’s Own Template

Meta’s launch materials describe two canonical use cases for text attachments: an author teasing a portion of a forthcoming novel, and a journalist promoting a think piece. Both are the same structural pattern: give enough substance to be worth the tap, hold enough back to justify the click to the full piece.

Opening lines of a novel tease using 10,000 characters:

“Chapter One The lighthouse had been dark for eleven years when Marguerite finally returned to relight it.” — that is 106 characters of 10,000. Most of a novel excerpt is atmosphere, not budget.

Inside the Attachment: Writing for the Tap-and-Scroll Reader

A reader who opens an attachment has made a commitment, but not an unlimited one. Write for someone who is deciding every paragraph whether to continue:

• Lead with the conclusion or the most quotable sentence, not with throat-clearing or context-setting. Context can come second.
• Use bold lines as headings — one per major section. It gives the reader a map they can use to decide whether to read carefully or skim.
• Keep paragraphs to 3 to 5 lines on a phone screen. Long paragraphs in a tap-to-expand block feel like punishment.
• End with a single clear action. Usually the link in the main post. Restating it at the end of the attachment closes the loop for readers who scrolled through and then forgot what to do.
• Use the Download .txt button in this tool to save a local copy of what you drafted — useful when the attachment is one section of a larger document you are serializing over multiple posts.

The SEO Angle: Google Indexes Public Threads Posts

Google now indexes public Threads posts. Within that reality, a public text attachment is the largest long-form writing surface Threads has, and its first paragraph does double duty: the same opening lines that serve as the feed preview also represent the post in search. Write the first paragraph as if it were a meta description — concrete language, the actual topic, the specific thing you are analyzing. The rest of the attachment can have whatever rhythm serves the reader. The opening lines serve two masters: the Threads feed preview and Google’s index.

Who Uses Text Attachments and How: Use Cases by Profession

Authors and Writers

Text attachments are built for book promotion. Share a chapter excerpt — 3,000 to 5,000 characters covers the opening hook of most chapters — with the pre-order or purchase link in the main post. The excerpt proves the writing is worth buying. The link closes the loop. No separate page needed, no leaving Threads.

Journalists and Media Professionals

An attachment works as a native think piece or op-ed. Publish the argument fully in the attachment, put the sharpest line as the main post hook, and link to the full published piece for readers who want sources and context. The attachment builds credibility with the writing; the link sends committed readers to the full version.

Newsletter Writers and the Creator Economy

The tease-and-subscribe pattern is the natural fit. Share one strong section of the current issue in the attachment — enough to demonstrate value, not enough to replace the newsletter. Put the subscribe link in the main post. Readers who find the content on Threads convert to subscribers; subscribers get the full version. The attachment is a sample, not a substitute.

Educators and Researchers

A 10,000-character attachment is enough space for a complete lesson unit: concept introduction, worked examples, common mistakes, and a summary. Format it with bold section headings and short paragraphs for mobile readability. For researchers, the attachment is a place to share findings and methodology in a format that is searchable and citable — more durable than a thread chain, more accessible than a paywalled paper.

Podcast Hosts and Audio Creators

The episode summary use case is underutilized. A complete transcript of the key ten minutes of an episode, formatted with speaker labels in bold, gives listeners a searchable reference and gives non-listeners a reason to engage with the episode’s content on Threads before deciding to listen. The episode link goes in the main post.

How to Use This Counter

The tool above has three modes that match the Threads two-field writing system:

• Text Attachment mode (10,000 characters, the default): counts your attachment text with the full progress bar, word count, reading time, speaking time, emoji count, and the unique-link tally against the 5-link cap. The format advisor tells you whether the draft fits the attachment, needs trimming, or should be a thread chain instead.
• Post mode (500 characters): counts your main post with the feed-fold marker at approximately 175 characters. Switch to this mode to draft the hook that introduces your attachment — the same 500-character field the parent Threads counter covers in depth.
• Reply mode (500 characters): same counting rules as Post mode. Use when drafting a long reply that will carry its own attachment.

Five features do the work the in-app editor does not provide:

• Live character count from the first keystroke, with a color-coded progress bar that shifts to warning at 85% and danger at 100% — and, in Attachment mode, a shaded band marking the focused 1,500 to 3,000-character range where most attachments perform best.
• Link tally — applies Meta’s documented unique-URL dedup logic across your draft and warns as you approach the shared 5-link cap.
• Format advisor — converts your character count into a decision: fits the post, fits the attachment, or needs a thread chain of N posts.
• Attachment preview — shows how your draft’s opening lines will appear inside the feed’s tap-to-expand gray block.
• Download .txt — saves a clean local copy of exactly what you typed, useful for writers managing long-form content across multiple posts.

Four quieter signals run alongside them: a hashtag line that counts how many characters your hashtags consume (with the one-topic-tag-per-post rule and its no-periods, no-ampersands restriction), an amber warning when complex emoji — flags, skin tones, ZWJ families — are detected in your draft, a paragraph-length flag when a single block runs long enough to become a wall of text on a phone, and a fediverse note that appears after you have been drafting for ten minutes or more, reminding you that posts only syndicate after the edit window closes. Copy, Clear, and Share buttons are available in every mode. The Share button encodes your draft into a URL parameter that you can send to a collaborator or save for later — the draft opens in the counter exactly as you left it — and your text also autosaves to this device as you type, so an accidental refresh mid-draft is recoverable from the banner above the editor.