Platform Limits

Every platform has rules. Some are sensible, some are arbitrary. We enforce them so you don’t get banned.

How Validation Works

We validate everything before sending to the platform. If your content breaks a rule, you get a 400 error with a clear message telling you exactly what’s wrong. Here’s the vocabulary:

Aspect Ratio: width / height. A 1920x1080 video has a ratio of ~1.78 (16:9).
Bitrate: (fileSize x 8) / videoLength. Measured in bps. We show it in Mbps.
File Count: How many images/videos you can attach to a single post.

Upload ceiling. Regardless of platform, the largest file we accept is 5 GB for video, 25 MB for images, and 100 MB for documents (PDF). The per-platform limits below are often lower - we enforce the smaller of the two.

Instagram

Posts (Carousel)

Constraint	Value
Files	1-10 (images and/or videos, mixed allowed)
Image max size	8 MB
Image max width	1920px
Image aspect ratio	4:5 to 1.91:1
Video max width	1920px
Video max bitrate	45 Mbps
Video duration	3s - 15 min
Video aspect ratio	0.01:1 to 10:1

Reels

Constraint	Value
Files	1 video (required)
Max width	1920px
Max bitrate	45 Mbps
Duration	3s - 15 min
Aspect ratio	0.01:1 to 10:1

Aspect ratios are law. Instagram is SUPER strict. If your pixel math is off by even a tiny bit, they might reject it. 9:16 vertical is the safe bet for Reels.

Stories

Constraint	Value
Files	1 (image or video)
Image max size	8 MB
Image aspect ratio	0.01:1 to 10:6
Video max size	100 MB
Video max width	1920px
Video max bitrate	25 Mbps
Video duration	3s - 60s
Video aspect ratio	0.01:1 to 10:6

TikTok

Videos

Constraint	Value
Files	1 video (required)
Max size	1 GB
Resolution	360x360 to 4096x4096
Aspect ratio	0.01:1 to 10:6
Duration	Max 10 min (600s)

Images (Photo Mode)

Constraint	Value
Files	1-10 images
Format	JPG/JPEG/WebP only - PNG and other formats will be rejected for TikTok Photo Mode
Max size	20 MB each
Max width	1920px

PNG is not valid for TikTok Photo Mode. Convert PNG assets before creating the TikTok image post.

YouTube

Shorts

Constraint	Value
Files	1 video (required)
Max size	5 GB
Duration	Max 3 min (180s)
Aspect ratio	1:3 to 1:1 (vertical or square)

Long Form Videos

Constraint	Value
Files	1 video (required)
Max size	5 GB
Duration	Max 4 hours (14,400s)
Aspect ratio	1:3 to 3:1

Constraint	Value
Files	0-10 (images, videos, OR documents - not mixed)
Videos
Max videos	1
Video max size	2 GB
Video resolution	256x144 to 4096x4096
Video aspect ratio	1:2.4 to 2.4:1
Video duration	3s - 30 min
Images
Max images	10
Image max size	5 MB each
Image min resolution	200x200
Documents
Max documents	1
Document max size	100 MB
Document format	PDF only

Twitter / X

Constraint	Value
Files	0-4 (images and/or videos)
Videos
Video max size	512 MB
Video aspect ratio	1:3 to 3:1
Video min length	0.5s
Video duration (Free/Basic)	Max 140s (2:20)
Video duration (Premium/Premium+)	Max 600s (10 min)
Images
Image max size	5 MB each
Max images	4
Text
Text limit (Free/Basic)	280 characters
Text limit (Premium/Premium+)	25,000 characters

Facebook

Page Posts

Constraint	Value
Files	0-10 (images or videos, not mixed)
Max videos	1
Video max bitrate	45 Mbps
Video aspect ratio	0.01:1 to 1.91:1
Video duration	Max 20 min (1,200s)
Max images	4
Image max size	4 MB each
Image aspect ratio	0.01:1 to 1.91:1

Reels

Constraint	Value
Files	1 video (required)
Min resolution	540x960
Aspect ratio	0.01:1 to 10:6
Max bitrate	45 Mbps
Duration	3s - 20 min (1,200s)

Stories

Constraint	Value
Files	1 (image or video)
Video min resolution	540x960
Video max bitrate	25 Mbps
Video duration	3s - 60s
Video aspect ratio	0.01:1 to 10:6
Image max size	4 MB
Image aspect ratio	0.01:1 to 10:6

Constraint	Value
Files	1 (image or video, required)
Videos
Video max size	2 GB
Video aspect ratio	1:2 to 1.91:1
Video duration	4s - 15 min (900s)
Images
Image max size	5 MB

Board name required. You can’t pin to thin air. Every Pinterest post needs boardName from socialAccount.channels.

Single Post

Constraint	Value
Files	0-1 (image or video)
Video max size	1 GB
Video aspect ratio	9:16 to 16:9
Video duration	4s - 15 min (900s)
Image max size	20 MB

Gallery Post

Constraint	Value
Files	0-10 images (only if subreddit allows galleries)
Image max size	20 MB each

Subreddit rules apply. Not all subreddits allow media, and not all allow galleries. We validate against the subreddit’s settings. If the subreddit requires a flair, you need to provide one.

Threads

Constraint	Value
Files	0-10 (images and/or videos, mixed allowed)
Video max size	1 GB
Video max bitrate	100 Mbps
Video aspect ratio	0.01:1 to 1.91:1
Image max size	8 MB
Image width	320-1440px
Image aspect ratio	0.01:1 to 1.91:1

Discord

Constraint	Value
Files	0-10 (images and/or videos, mixed allowed)
Video max size	25 MB
Video aspect ratio	0.01:1 to 1.91:1
Image max size	25 MB
Image aspect ratio	0.01:1 to 1.91:1
Text	Max 2,000 characters

Channel ID required. Discord posts go to a specific channel. Check socialAccount.channels for available options.

Slack

Constraint	Value
Files	0-4 (images and/or videos, mixed allowed)
Video max size	1 GB
Video aspect ratio	0.01:1 to 1.91:1
Image max size	1 GB
Image aspect ratio	0.01:1 to 1.91:1
Text	Max 30,000 characters

Mastodon

Constraint	Value
Files	0-4 (images and/or videos, mixed allowed)
Max videos	1
Video max size	99 MB
Video aspect ratio	1:3 to 1:1
Max images	4
Image max size	16 MB each
Text	Instance-dependent (usually 500 chars)

Bluesky

Constraint	Value
Files	0-4 (images and/or videos)
Text	300 characters

Bluesky has minimal media restrictions on their end. We enforce basic file count limits, but the platform is relatively permissive compared to others.

Google Business

Constraint	Value
Files	0-1 image only (no video)
Image max size	5 MB
Image min resolution	250x250
Text	Max 1,500 characters

Snapchat

Stories

Constraint	Value
Files	Exactly 1 image or MP4 video
Max file size	100 MB
Video minimum resolution	540x960
Video duration	5-60 seconds

Spotlights

Constraint	Value
Files	Exactly 1 MP4 video
Max file size	100 MB
Minimum resolution	540x960
Video duration	6-60 seconds

Quick Reference Table

Platform	Max Files	Video Max Size	Video Max Duration	Image Max Size
Instagram Post	10	N/A (bitrate limit)	15 min	8 MB
Instagram Reel	1	N/A (bitrate limit)	15 min	-
Instagram Story	1	100 MB	60s	8 MB
TikTok Video	1	1 GB	10 min	-
TikTok Image	10	-	-	20 MB
YouTube Short	1	5 GB	3 min	-
YouTube Video	1	5 GB	4 hours	-
LinkedIn	10	2 GB	30 min	5 MB
Twitter/X	4	512 MB	140s / 10 min	5 MB
Facebook Post	10	N/A (bitrate limit)	20 min	4 MB
Facebook Reel	1	N/A (bitrate limit)	20 min	-
Facebook Story	1	N/A (bitrate limit)	60s	4 MB
Pinterest	1	2 GB	15 min	5 MB
Reddit	1 / 10 gallery	1 GB	15 min	20 MB
Threads	10	1 GB	-	8 MB
Discord	10	25 MB	-	25 MB
Slack	4	1 GB	-	1 GB
Mastodon	4	99 MB	-	16 MB
Bluesky	4	-	-	-
Google Business	1	-	-	5 MB
Snapchat Story	1	100 MB	60s	100 MB
Snapchat Spotlight	1	100 MB	60s	-

Text & Character Limits

Platform	Main text field limit	Other text field limits
Instagram	`text`: 2,000	`collaborators` username max 30, `tagged` username max 30, optional `altText` on image posts
TikTok	`text`: 2,200	-
YouTube	`text` (title): 100	`description`: 5,000
LinkedIn	`text`: 3,000	`mediaTitle`: 200
Twitter / X	`text`: 280 (Free/Basic), 25,000 (Premium/Premium+)	-
Facebook	`text`: 50,000	`mediaTitle`: 255, `link`: 2,048, optional `altText` on image posts
Pinterest	`text`: 100	`description`: 800, `altText`: 500, `note`: 500
Reddit	`text` (title): 300	`description`: 30,000
Threads	`text`: 500	optional `altText` on image media
Discord	`text`: 2,000	`username`: 80, `avatarUrl`: 2,048
Slack	`text`: 30,000	`username`: 80, `avatarUrl`: 2,048
Mastodon	`text`: 30,000	`spoiler`: 50 (instance-level limits can still be lower)
Bluesky	`text`: 300	`externalTitle`: 300, `externalDescription`: 1,000, `videoAlt`: 10,000
Google Business	`text`: 1,500	`eventTitle`: 58, `offerCouponCode`: 58, `offerTermsConditions`: 1,500
Snapchat	`description` or `text`: 160	`locale`: `en_US` format for Spotlights

For daily posting limits per platform and monthly post caps, see Rate Limits.

API Documentation

Platforms

Guides

Endpoints

How Validation Works

Instagram

Posts (Carousel)

Reels

Stories

TikTok

Videos

Images (Photo Mode)

YouTube

Shorts

Long Form Videos

LinkedIn

Twitter / X

Facebook

Page Posts

Reels

Stories

Pinterest

Reddit

Single Post

Gallery Post

Threads

Discord

Slack

Mastodon

Bluesky

Google Business

Snapchat

Stories

Spotlights

Quick Reference Table

Text & Character Limits

​How Validation Works

​Instagram

​Posts (Carousel)

​Reels

​Stories

​TikTok

​Videos

​Images (Photo Mode)

​YouTube

​Shorts

​Long Form Videos

​LinkedIn

​Twitter / X

​Facebook

​Page Posts

​Reels

​Stories

​Pinterest

​Reddit

​Single Post

​Gallery Post

​Threads

​Discord

​Slack

​Mastodon

​Bluesky

​Google Business

​Snapchat

​Stories

​Spotlights

​Quick Reference Table

​Text & Character Limits

How Validation Works

Instagram

Posts (Carousel)

Reels

Stories

TikTok

Videos

Images (Photo Mode)

YouTube

Shorts

Long Form Videos

LinkedIn

Twitter / X

Facebook

Page Posts

Reels

Stories

Pinterest

Reddit

Single Post

Gallery Post

Threads

Discord

Slack

Mastodon

Bluesky

Google Business

Snapchat

Stories

Spotlights

Quick Reference Table

Text & Character Limits