What is the character limit difference between Mastodon and Telegram?

Mastodon allows 500 characters and Telegram allows 4,000.

How do I post to Mastodon and Telegram at the same time?

With PostWire, one API call publishes to both: POST /api/post with platforms set to ["mastodon","telegram"]. Or one MCP tool call from an AI agent.

Works, with rewrites

Cross-posting Mastodon to Telegram: what actually breaks

You can, but not by copying the text across: 2 things change between Mastodon and Telegram, starting with you have 3,500 characters you are not using. Below is exactly what breaks and what to do instead.

Side by side

	Mastodon	Telegram
Characters	500	4,000
Media	optional	optional
Hashtags	2-4 hashtags in CamelCase (#SocialMedia, not #socialmedia) for screen readers	not needed
Links in body	fine	fine
Needs platform approval	no	no

What changes, one by one

You have 3,500 characters you are not using

Mastodon caps at 500 characters, Telegram allows 4,000. Posting the short version verbatim wastes the room Telegram gives you to actually explain the thing.

The hashtag rules are not the same

Mastodon: 2-4 hashtags in CamelCase (#SocialMedia, not #socialmedia) for screen readers. Telegram: not needed. Carrying the tag block across is the single most obvious sign of an automated cross-post.

Why copy-paste cross-posting underperforms

Mastodon is community-first; alt text on media is expected, not optional. Telegram is direct and clear; formatting is light. Those are different jobs, so the same words cannot do both well — and every algorithm here demotes text that obviously was not written for it. The fix is not to skip cross-posting; it is to send a native version to each network.

Publish to both in one call

curl -X POST https://postwire.io/api/post \
  -H "Authorization: Bearer $POSTWIRE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "platforms": ["mastodon", "telegram"],
    "text": "Your post",
    "per_platform": {
      "mastodon": { "text": "The Mastodon version" },
      "telegram": { "text": "The Telegram version" }
    }
  }'

PostWire's /api/generate writes those per-platform versions for you from a single prompt, respecting every limit in the table above. From an AI agent it is one MCP tool call.

Get an API key free →

Questions people actually ask

Can I cross-post from Mastodon to Telegram?: You can, but not by copying the text across: 2 things change between Mastodon and Telegram, starting with you have 3,500 characters you are not using. Below is exactly what breaks and what to do instead.
What is the character limit difference between Mastodon and Telegram?: Mastodon allows 500 characters and Telegram allows 4,000.
How do I post to Mastodon and Telegram at the same time?: With PostWire, one API call publishes to both: POST /api/post with platforms set to ["mastodon","telegram"]. Or one MCP tool call from an AI agent.

Other pairs: Telegram to Mastodon · all combinations · which APIs need approval