Validate post character count
Check weighted character count per platform and whether the text is within each platform's limit. Twitter/X uses weighted counting (URLs = 23 chars via t.co, emojis = 2 chars). All other platforms use plain character length. Returns counts and limits for all 15 supported platform variants.
API key authentication - use your Late API key as a Bearer token
In: header
The post text to check
Response Body
application/json
curl -X POST "https://getlate.dev/api/v1/tools/validate/post-length" \ -H "Content-Type: application/json" \ -d '{ "text": "Check out https://getlate.dev for scheduling posts!" }'{
"text": "string",
"platforms": {
"twitter": {
"count": 51,
"limit": 280,
"valid": true
},
"twitterPremium": {
"count": 51,
"limit": 25000,
"valid": true
},
"instagram": {
"count": 51,
"limit": 2200,
"valid": true
},
"bluesky": {
"count": 51,
"limit": 300,
"valid": true
},
"snapchat": {
"count": 51,
"limit": 160,
"valid": true
}
}
}Validate media URL POST
Check if a media URL is accessible and return metadata (content type, file size) plus per-platform size limit comparisons. Performs a HEAD request (with GET fallback) to detect content type and size. Rejects private/localhost URLs for SSRF protection. Platform limits are sourced from each platform's actual upload constraints.
Validate post content POST
Dry-run the full post validation pipeline without publishing. Catches issues like missing media for Instagram/TikTok/YouTube, hashtag limits, invalid thread formats, Facebook Reel requirements, and character limit violations. Accepts the same body as `POST /v1/posts`. Does NOT validate accounts, process media, or track usage. This is content-only validation. Returns errors for failures and warnings for near-limit content (>90% of character limit).