Threads opened its API in 2024 and it is one of the better-behaved ones: text, pictures, video, carousels up to twenty items, polls, reply chains, and figures back. It also has two rules that trip people who come from Instagram, and they are both about counting.
The 500 that is really bytes
Threads allows 500 characters and counts them as UTF-8 bytes. Letters cost one, accented letters cost two, most emoji cost four. A post of 480 characters with six emoji is over the limit and the API refuses it, while a counter that counts characters says 480. Preflight counts bytes for Threads, so the figure next to the box is the one the API sees.
Five links
Since late 2025 a Threads post can contain at most five links; a sixth makes the API refuse the post. Most composers do not check this and surface it as a failure afterwards.
What a post can hold
| Limit | |
|---|---|
| Text | 500 bytes; optional when the post has media |
| Pictures | Up to 20 in a carousel; JPEG or PNG, 8 MB, ratio up to 10:1, width 320 to 1,440 (Threads resizes outside that) |
| Video | MP4 or MOV, up to 1 GB and 5 minutes, 23 to 60 fps |
| Links | 5 |
| Polls | Up to 4 options, text posts only |
| Threads | A chain of replies posted in order |
| Reply control | Everyone, people you follow, mentioned only, or (since 2026) the parent post's author only |
| Topic | A topic tag on the post |
| Alt text | Per picture or video |
| Editing | Not in the API; delete and re-post |
Publishing is a two-step on Threads' side: the tool creates a container, waits for Threads to process the media, then publishes it. Video can take a minute. A scheduler that does not wait publishes an empty container and reports success; Preflight polls until the container is ready and reports what Threads said.
Scheduling it
Threads has no scheduling of its own, so the tool posts at the time. In Preflight, Threads is a channel with its own settings card: reply control, topic, poll options, and a thread editor for chains. The byte count, the five-link rule, the picture formats and the fps window are checked while you type, with Instagram and Facebook variants of the same caption beside it if the post goes there too.
Comments and figures
Replies are readable and answerable, and a reply can be hidden. Figures: views, likes, replies, reposts and quotes per post, and daily follower counts. Threads reports views, which Bluesky and Mastodon do not.
Which schedulers support Threads
Nearly all of them in 2026: Buffer, Preflight, Publer, Metricool, Later, Postiz, PostFast, Post Bridge, SocialBee, Vista Social, Hootsuite, Typefully, Blotato, Kontentino. The differences are in polls, carousels past ten items, reply control, the thread editor, and whether the counter counts bytes.
Questions people ask
- What is the Threads character limit?
- 500, counted as UTF-8 bytes. Plain Latin letters cost one byte each; an accented letter two; most emoji four.
- Can Threads posts be scheduled natively?
- The Threads app has drafts but no scheduler for everyone; the API has none. A tool posts at the scheduled time.
- Can a scheduler post a poll to Threads?
- Yes, through the API, on text posts: up to four options. Preflight exposes it on the Threads settings card.