Free tool
Will it post?
Drop a video or an image to see whether Instagram, TikTok, YouTube, LinkedIn, Facebook, Bluesky, and Pinterest will take it: file type, size, dimensions, aspect ratio and length, checked against the limits each network publishes, with the exact rule it breaks and how to fix it. The file is read in your browser and never uploaded.
Last checked against each network's documentation on .
Limits
What each network accepts
Every rule below is quoted from the network's own developer or help page, linked beside it. Where a network's API reference and its help centre disagree, the API reference wins, because that is what a scheduler publishes through.
| Rule | Source |
|---|---|
| MP4 (recommended), WebM or MOV. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| At most 4 GB. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Between 360 and 4096 pixels wide. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Between 360 and 4096 pixels tall. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Between 23 and 60 frames per second. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| At most 10 minutes: the longest video the upload endpoint accepts. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Every creator can post 3-minute videos; only some accounts can post 5- or 10-minute ones.(warning, not a refusal) | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Codec: H.264 (recommended), H.265, VP8 or VP9.(not readable in a browser) | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Rule | Source |
|---|---|
| JPEG or WebP. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| At most 20 MB per image. | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Maximum 1080p (TikTok does not say which side; this checks the shorter one).(warning, not a refusal) | TikTok for Developers: Content Posting API media transfer guide, checked 2026-10-21 |
| Rule | Source |
|---|---|
| JPEG only. Extended JPEG formats such as MPO and JPS are not supported. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| At most 8 MB. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Aspect ratio between 4:5 (portrait) and 1.91:1 (landscape). | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| 320 to 1440 pixels wide; anything outside is scaled to fit.(warning, not a refusal) | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Rule | Source |
|---|---|
| MOV or MP4, with the moov atom at the front of the file and no edit lists. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| At most 300 MB. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Between 3 seconds and 15 minutes. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| At most 1920 pixels wide. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Aspect ratio between 0.01:1 and 10:1; 9:16 is recommended to avoid cropping or blank space. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Between 23 and 60 frames per second. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| HEVC or H.264, progressive scan, closed GOP, 4:2:0; variable bitrate up to 25 Mbps; AAC audio at up to 48 kHz.(not readable in a browser) | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Rule | Source |
|---|---|
| MOV or MP4, same encoding as Reels. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| At most 100 MB. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Between 3 and 60 seconds. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Aspect ratio between 0.1:1 and 10:1; 9:16 is recommended. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Between 23 and 60 frames per second. | Meta for Developers: Instagram Graph API, IG User Media reference, checked 2026-10-21 |
| Rule | Source |
|---|---|
| JPEG, BMP, PNG, GIF or TIFF. | Meta for Developers: Graph API, Page photos reference, checked 2026-10-21 |
| At most 10 MB. | Meta for Developers: Graph API, Page photos reference, checked 2026-10-21 |
| Rule | Source |
|---|---|
| MP4 is the recommended file type.(warning, not a refusal) | Meta for Developers: Reels publishing guide, checked 2026-10-21 |
| Between 3 and 90 seconds. | Meta for Developers: Reels publishing guide, checked 2026-10-21 |
| At least 540 pixels wide (1080 recommended). | Meta for Developers: Reels publishing guide, checked 2026-10-21 |
| At least 960 pixels tall (1920 recommended). | Meta for Developers: Reels publishing guide, checked 2026-10-21 |
| 9:16 is the stated ratio; the guide's error table refuses anything outside 16:9 to 9:16. | Meta for Developers: Reels publishing guide, checked 2026-10-21 |
| Between 24 and 60 frames per second. | Meta for Developers: Reels publishing guide, checked 2026-10-21 |
| H.264 or H.265 (VP9 and AV1 also supported), 4:2:0, closed GOP, fixed frame rate; AAC-LC audio at 48 kHz, 128 kbps or more.(not readable in a browser) | Meta for Developers: Reels publishing guide, checked 2026-10-21 |
| Rule | Source |
|---|---|
| JPG, GIF or PNG. | Microsoft Learn: LinkedIn Marketing API, Images API, checked 2026-10-21 |
| Fewer than 36,152,320 pixels in total. | Microsoft Learn: LinkedIn Marketing API, Images API, checked 2026-10-21 |
| Rule | Source |
|---|---|
| MP4. | Microsoft Learn: LinkedIn Marketing API, Videos API, checked 2026-10-21 |
| Between 75 KB and 500 MB. | Microsoft Learn: LinkedIn Marketing API, Videos API, checked 2026-10-21 |
| Between 3 seconds and 30 minutes. | Microsoft Learn: LinkedIn Marketing API, Videos API, checked 2026-10-21 |
| Rule | Source |
|---|---|
| Any video MIME type. | YouTube Data API: videos.insert, checked 2026-10-21 |
| Up to 3 minutes; a longer video is uploaded as a regular video, not a Short. | YouTube Help: Upload YouTube Shorts, checked 2026-10-21 |
| Square or vertical; a landscape video is not a Short. | YouTube Help: Upload YouTube Shorts, checked 2026-10-21 |
| Shorts are uploaded at up to 1080p.(warning, not a refusal) | YouTube Help: Get started with YouTube Shorts, checked 2026-10-21 |
| At most 256 GB. | YouTube Data API: videos.insert, checked 2026-10-21 |
| Rule | Source |
|---|---|
| PNG or JPEG. | Pinterest Help: Pinterest product specs, checked 2026-10-21 |
| At most 20 MB (Pinterest states 20 MB on desktop, 32 MB in its app). | Pinterest Help: Pinterest product specs, checked 2026-10-21 |
| 2:3 (for example 1000 × 1500) is recommended; a Pin taller than 2:3 might get cut off.(warning, not a refusal) | Pinterest Help: Pinterest product specs, checked 2026-10-21 |
| Rule | Source |
|---|---|
| MP4, MOV or M4V, encoded H.264 or H.265. | Pinterest Help: Pinterest product specs, checked 2026-10-21 |
| Up to 2 GB. | Pinterest Help: Pinterest product specs, checked 2026-10-21 |
| Between 4 seconds and 15 minutes. | Pinterest Help: Pinterest product specs, checked 2026-10-21 |
| Square (1:1) or vertical (2:3, 4:5 or 9:16) is recommended.(not readable in a browser) | Pinterest Help: Pinterest product specs, checked 2026-10-21 |
| Rule | Source |
|---|---|
| Any image type. | Bluesky AT Protocol lexicon: app.bsky.embed.images, checked 2026-10-21 |
| At most 2 MB (2,000,000 bytes) per image. | Bluesky AT Protocol lexicon: app.bsky.embed.images, checked 2026-10-21 |
| Rule | Source |
|---|---|
| MP4. | Bluesky AT Protocol lexicon: app.bsky.embed.video, checked 2026-10-21 |
| At most 300 MB (300,000,000 bytes). | Bluesky AT Protocol lexicon: app.bsky.embed.video, checked 2026-10-21 |
| Up to 3 minutes. | Bluesky's official account (@bsky.app), 2025-03-10, checked 2026-10-21 |
Questions
Media limits, answered
Is my video or image uploaded anywhere?
No. The checker reads the file's type, size, width, height and length in your browser and compares them with each network's published limits. The file itself never leaves your device.
Where do these limits come from?
From each network's own developer documentation and help pages, never from third-party guides. Every rule links the page it was read on, and all of them were last checked on 2026-10-21. Where a network's API reference and its help centre disagree, the API reference wins, because that is what a scheduling tool publishes through.
Why does a check say a rule was not measured?
A browser can read a file's type, size, dimensions and duration, but not its frame rate, codec or bitrate. Those rules are listed so you know they exist; check them in your editor's export settings. If you call the API, you can send the frame rate and it is checked too.
What is the difference between a failure and a warning?
A failure means the network's documentation says it refuses a file like this. A warning means the network says the file may be cropped or downscaled, or that only some accounts can post it, such as TikTok videos longer than 3 minutes.
Can I run the check from code?
Yes. Send the file's metadata (type, size, width, height, duration and optionally frame rate) to https://usepostify.com/api/tools/validate-media. No API key is needed, the response is JSON (or Markdown with Accept: text/markdown), and no file is ever uploaded.
Requirements by network
Run it from code
The same check is a free API: send the file's metadata, never the file. No key, JSON by default, Markdown with Accept: text/markdown.
curl -s "https://usepostify.com/api/tools/validate-media?type=video/mp4&bytes=48000000&width=1080&height=1920&duration=42"
Then schedule it in Postify
Once the file fits, Postify publishes it to every network from one composer, each with its own caption. There is a free plan with no credit card required.