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Post preview checker

Type a caption and watch it against every platform's real limit: characters, where Instagram and LinkedIn cut it off, hashtags, mentions and links. The limits are the ones Postwoo enforces before it schedules a post.

0 characters · 0 hashtags · 0 mentions · 0 links

Platforms
Attachment

Counts update as you type. The full check also runs Postwoo's composer pre-flight for each platform. Nothing is saved.

Google

Fits

0 / 1,500 characters · 1,500 left

  • Hashtags0 · suggested 0
  • Mentions0
  • Links in text0

Run the full check to see Postwoo's pre-flight for Google.

Google Business Profile rules
  • Images must be at least 250×250 px and publicly reachable by URL.
  • Posts expire after 7 days unless they are EVENT or OFFER posts with a schedule.
  • Phone numbers in the post text are rejected by Google.
  • Hashtags are not clickable on Google Business Profile posts and are discouraged. (guidance, not a documented API limit)
Scheduling to Google with Postwoo →

Facebook

Fits

0 / 63,206 characters · 63,206 left

  • Hashtags0 · suggested 1–3
  • Mentions0
  • Links in text0

Run the full check to see Postwoo's pre-flight for Facebook.

Facebook Pages rules
  • Photos are fetched by Facebook from a public HTTPS URL (JPEG/PNG/GIF/WEBP, ≤10 MB recommended).
  • A link preview is generated by Facebook from the link; it cannot be customised by most apps.
  • When a photo and a link are both present, the link is appended to the caption (the photos endpoint has no link field).
  • Hashtags are clickable but rarely drive discovery on Pages; keep it to 1–3. (guidance, not a documented API limit)
Scheduling to Facebook with Postwoo →

Instagram

Needs media

0 / 2,200 characters · 2,200 left

  • Hashtags0 / max 30 · suggested 3–5
  • Mentions0 / max 20
  • Links in text0
Feed preview (about 125 characters or 2 lines — a rule of thumb)

Your caption preview appears here.

Run the full check to see Postwoo's pre-flight for Instagram.

Instagram Professional rules
  • Captions: up to 2,200 characters, at most 30 hashtags and 20 @mentions.
  • Images: JPEG only, ≤8 MB, width 320–1440 px, aspect ratio between 4:5 and 1.91:1.
  • Video is published as a Reel: MP4/MOV, H.264 + AAC, 3 seconds – 15 minutes, ≤1 GB, 9:16 recommended.
  • Instagram allows 25 API-published posts per account per rolling 24 hours (GET /{ig-user-id}/content_publishing_limit).
  • Media must be downloadable by Meta from a public HTTPS URL.
  • At most 30 hashtags across the caption and the first comment. Instagram recommends 3–5 relevant hashtags.
Scheduling to Instagram with Postwoo →

LinkedIn

Fits

0 / 3,000 characters · 3,000 left

  • Hashtags0 · suggested 3–5
  • Mentions0
  • Links in text0
Feed preview (about 210 characters or 3 lines — a rule of thumb)

Your caption preview appears here.

Run the full check to see Postwoo's pre-flight for LinkedIn.

LinkedIn rules
  • Commentary is limited to 3,000 characters; LinkedIn markup characters are escaped automatically.
  • An article (link) post needs the link plus a title; LinkedIn fetches the preview itself.
  • Multi-image (up to 20) and video posts are possible in the API but not built yet.
  • Member (personal profile) posts cannot be measured; analytics are available for organization Pages only.
  • Use 3–5 specific hashtags; LinkedIn has no published hard cap. (guidance, not a documented API limit)
Scheduling to LinkedIn with Postwoo →

YouTube

Needs media

0 / 5,000 characters · 5,000 left

  • Hashtags0 / max 15 · suggested 3
  • Mentions0
  • Links in text0

Run the full check to see Postwoo's pre-flight for YouTube.

YouTube rules
  • Exactly one video per post. Title (≤100 characters, no < or >) comes from options.title; the post body becomes the description (≤5,000 characters).
  • YouTube accepts files up to 256 GB; Postwoo caps uploads at 2 GB because the file is streamed through this server in one PUT.
  • Videos from unaudited API projects are forced to private visibility by YouTube.
  • videos.insert costs ~1,600 quota units of the default 10,000/day.
  • Up to 15 hashtags in the description (YouTube ignores all of them beyond that); the first 3 are shown with the title.
Scheduling to YouTube with Postwoo →

TikTok

Needs media

0 / 2,200 characters · 2,200 left

  • Hashtags0 · suggested 3–5
  • Mentions0
  • Links in text0

Run the full check to see Postwoo's pre-flight for TikTok.

TikTok rules
  • Exactly one video per post (MP4, MOV or WEBM; H.264/H.265 + AAC; 3 seconds – 10 minutes, ≤4 GB). The creator's own maximum duration is returned by creator_info/query.
  • Captions (title) are limited to 2,200 characters including hashtags and @mentions.
  • PULL_FROM_URL requires the media host to be a verified domain of the TikTok app; otherwise use FILE_UPLOAD (planned).
  • Unaudited apps: posts are forced to SELF_ONLY and limited to a handful of posts per day.
  • Rate limit: 6 requests per minute per user token on the Content Posting API.
  • Hashtags go in the caption and count towards the 2,200-character caption limit.
Scheduling to TikTok with Postwoo →

Threads

Fits

0 / 500 characters · 500 left

  • Hashtags0 / max 1 · suggested 1
  • Mentions0
  • Links in text0

Run the full check to see Postwoo's pre-flight for Threads.

Threads rules
  • Text: up to 500 characters (Threads counts characters, including the appended link when media is attached).
  • Images: JPEG or PNG, ≤8 MB, aspect ratio between 10:1 and 1:10, width ≤1440 px recommended. Video: MP4/MOV, H.264 + AAC, ≤1 GB, ≤5 minutes.
  • Two or more media items become a carousel (images and videos may be mixed). Postwoo caps carousels at 10 items; the API documents up to 20.
  • A link is attached as a preview card on text-only posts (link_attachment); with media it is appended to the text.
  • Media must be downloadable by Meta from a public HTTPS URL (APP_URL / S3), exactly like Instagram.
  • Threads allows 250 API-published posts per profile per rolling 24 hours (plus 1,000 replies).
  • Threads supports a single topic tag per post (assumption — verify against current Threads behaviour). (guidance, not a documented API limit)
Scheduling to Threads with Postwoo →

Pinterest

Needs media

0 / 800 characters · 800 left

  • Hashtags0 · suggested 0
  • Mentions0
  • Links in text0

Run the full check to see Postwoo's pre-flight for Pinterest.

Pinterest rules
  • Every pin needs a board: pick one in the composer (boards are discovered as locations) or set platform option board_id.
  • One pin per API call: title ≤100 characters, description (the post body) ≤800, alt text ≤500, one destination link.
  • Images: JPEG or PNG, 2:3 aspect ratio recommended (1000×1500 px), ≤20 MB (assumption). 2–5 images become a carousel pin.
  • Video: MP4/MOV, 4–15 minutes max depending on account, ≤2 GB; a cover image (first attached image) or key-frame time is used as the thumbnail. Video is uploaded directly and processed asynchronously.
  • Images are fetched by Pinterest from a public HTTPS URL (APP_URL / S3).
  • Trial-access apps must use the sandbox host (PINTEREST_API_BASE=https://api-sandbox.pinterest.com) and can only pin to their own test accounts.
  • Hashtags in Pin descriptions are plain text, not a discovery feature; write descriptive keywords instead. (guidance, not a documented API limit)
Scheduling to Pinterest with Postwoo →

Bluesky

Fits

0 / 300 graphemes · 300 left

  • Hashtags0 · suggested 1–3
  • Mentions0
  • Links in text0

Run the full check to see Postwoo's pre-flight for Bluesky.

Bluesky rules
  • Text: up to 300 graphemes (user-perceived characters; an emoji counts as one). Links, @mentions and #hashtags become rich-text facets automatically.
  • Images: up to 4 per post, uploaded directly as blobs of at most 1,000,000 bytes. Larger JPEG/PNG/WEBP/GIF files are re-encoded as JPEG and downscaled by Postwoo before upload (animated GIFs lose animation).
  • A link without images becomes a link card (title/description from the post's link fields; no thumbnail). With images the URL is added to the text instead — Bluesky allows one embed per post.
  • Video posts are planned (app.bsky.embed.video); attach no video for now.
  • Connections use an app password created at bsky.app → Settings → Privacy and security → App passwords — never the main password.
  • Rate limits (assumptions): createSession 30 per 5 minutes per account; createRecord about 1,666 per hour per account.
  • Hashtags are facets inside the post text, which is limited to 300 graphemes.
Scheduling to Bluesky with Postwoo →

Checks like these, on every post, for every client

Postwoo's composer runs this pre-flight for each platform before anything is queued, lets you tailor captions per platform and schedules to nine networks.

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FAQ

Questions, answered honestly

Where do the character limits come from?

From Postwoo's own platform integrations: the same limits the composer checks before a post can be scheduled, for example 2,200 characters on Instagram, 3,000 on LinkedIn, 500 on Threads and 300 graphemes on Bluesky.

How accurate is the "… more" preview?

It is a rule of thumb. Instagram and LinkedIn do not publish an exact cut-off, and it changes with screen size and line breaks. Treat it as "put the important part first", not a hard number.

Why does Bluesky count differently?

Bluesky limits posts to 300 graphemes — characters as you see them — so an emoji made of several code points counts as one. Other platforms count characters.

Is my caption saved?

No. Live counts happen in your browser. The full check sends the caption to Postwoo once, runs the checks and shows the result; nothing is stored.

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