# Slack character counter

Canonical: https://postmesh.app/tools/slack-character-counter

Paste your text to check it against Slack’s message limits, counted the way Slack counts.

## How it works

Where Slack publishes a limit, the counter links to the page that states it. Where Slack doesn’t publish one, the limit is marked as reported: it’s the number Slack’s app is widely reported to enforce, and the app has the final say.

Where Slack counts emoji or accented letters differently, the counter does the same. Nothing you type leaves your browser.

## Steps

1. Type or paste your text.

2. Read the count against each limit.

3. Shorten anything marked over.

## Slack limits at a glance

| Field | Limit | Basis |
| --- | --- | --- |
| Message | 40,000 characters | [Slack API: chat.postMessage](https://docs.slack.dev/reference/methods/chat.postMessage/) |

## Questions

### Where do these Slack limits come from?

From Slack’s own documentation where it publishes one, linked under the counter. The others are marked as reported because Slack doesn’t state them on a help page.

### Is my text saved?

No. The count runs in your browser.

### Does PostMesh post to Slack?

Not today. PostMesh publishes to Instagram, Facebook Pages, Threads, Reddit, X, LinkedIn, YouTube and TikTok.

Interactive controls are available on the HTML page. Image and text utilities run in the browser; AI writers submit descriptions to PostMesh and OpenAI.