Threads Character Limit 2026: 500 per Post, and Why Emoji Cost 4

Short answer: a Threads post holds 500 characters. The catch is emoji: Meta counts each one as its UTF-8 bytes, so 🎉 costs 4, ❤️ costs 6 and a family emoji costs 18. A post with 480 letters and ten 🎉 is 520 for Threads, and most counters that treat an emoji as 1 or 2 will tell you it fits. For longer ideas, attach up to 10,000 characters of text or continue in a reply. Paste a draft into the free social media character counter: its Threads row counts emoji the way Meta does.

Every Threads limit in one table#

These numbers come from Meta's developer documentation, which is the rulebook for every post a scheduling tool publishes. Third-party guides that say Threads "raised the limit to 10,000" mix up the post and the attachment, and the older "10 images" figure dates from before carousels went to 20.

How Threads counts the 500#

Letters, digits, spaces, punctuation and line breaks count as 1 each. Accented letters such as é or ü count as 1 too, even though they take 2 bytes: the byte rule applies to emoji only. Here is what common emoji cost, measured with the same rule PostBoost uses (each emoji's UTF-8 length):

So emoji eat the budget fast. Fifteen 🔥 cost 60, which leaves 440 characters for words. If a draft looks fine at 495 in another app and Threads refuses it, count the emoji again at 4 or more each.

Two things Meta does not spell out. It does not say whether links are shortened for the count, so plan for a link's full length, and long tracking links are a good reason to keep UTM parameters short. And the byte rule is written for posts made through the Threads API; the Threads app may count its own composer differently, but anything you schedule is published through the API.

When 500 is not enough#

You have two options, and they suit different posts.

A text attachment keeps the post as one unit: up to 10,000 characters of plain text below the post, plus one link of its own. Meta added it in September 2025 for "when 500 characters isn't enough". It works only on text-only posts, so not with images, video or a poll. You add it in the Threads app today; PostBoost publishes the post text, images, videos and reply chains, not text attachments.

A chain of replies is the classic thread: each reply has its own 500 characters and can carry its own images. It suits step-by-step posts, where every part should stand on its own in the feed. To split a long draft at sentence boundaries, paste it into the free thread maker and pick Threads as the network: it breaks at paragraphs, then sentences, never inside a word or link, keeps each part under 500 the way Threads counts them, and can add "1/5"-style numbers. The blog post to X thread guide covers how to write the first post so people open the rest; the same ideas work on Threads.

How PostBoost handles Threads limits#

PostBoost checks Threads' rules in the composer and again through the API.

• Hard limits in the composer. Over 500 characters, the Threads account shows "Maximum of 500 characters allowed." and the post cannot be scheduled until it is shorter. The same check allows up to 20 photos or videos in one post, mixed if you like, and videos up to 5 minutes.
• The emoji gap, and how it is caught. The composer counts an emoji as 2, so emoji-heavy text can fit there and still be over Meta's 500. Two checks catch it before Threads does. A post created or updated through the API comes back with a threads_too_long warning ("The Threads post is 520 characters as Threads counts them...") and is still saved, so you can shorten it. And the pre-publish checker agent (Tools → Agents) looks at scheduled posts and proposes holding one that Threads would reject; every proposal waits in the Approval queue for a person. See the agents docs.
• Reply chains. Click Add Post in the composer to add the next post of the chain. Each part is checked against the 500 on its own (an error reads "Post #2 - Maximum of 500 characters allowed."), and PostBoost publishes the parts as replies, in order. If the same post also goes to a Facebook, Instagram or LinkedIn account, the button reads Add first comment instead; create a version for the Threads account and add the replies there.
• Suggestions, not blocks. The composer flags images without alt text and says "Threads works best with no more than 1 hashtag, and this post has 2." when a post has two, which matches Threads' one-topic-tag rule. You can ignore a suggestion and still schedule.

To check one draft against Threads and every other network you post to, paste it into the free social media post checker. It applies the same length and media rules, with Threads emoji counted as bytes.

Catch the warning from the API#

If you schedule from a script or an AI agent, read warnings on the create response. Item 2 and later in content are the replies of the chain:

curl -X POST "https://postboost.co/app/api/$WORKSPACE_UUID/posts" \
  -H "Authorization: Bearer $POSTBOOST_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "accounts": [21],
    "versions": [{
      "account_id": 0,
      "is_original": true,
      "content": [
        { "body": "Five things we changed in our release process this quarter, and the one we rolled back. 🚀" },
        { "body": "1. We ship every Friday, not when a feature feels done. Smaller releases, fewer surprises." }
      ]
    }]
  }'

This saves a draft. When a part is over 500 the way Threads counts it, the response is still 201 and includes "warnings": [{"code": "threads_too_long", "account_id": 21, "message": "..."}]; shorten the part named in the message before you schedule. The network rules apply when you schedule ("schedule": true with a date and time): a part over 500 even at 2 per emoji is then refused with a validation error (createPost).

To plan Threads posts and reply chains with the limits checked for you, start free and connect your Threads account.