> ## Documentation Index
> Fetch the complete documentation index at: https://docs.letmepost.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# threads.text.max_graphemes

> Threads caps post text at 500 graphemes, including image captions.

## What it checks

`countGraphemes(text) <= 500` regardless of post shape (text-only, image, video, carousel).

## Why 500

Meta's published Threads API documents the 500-character cap. We use grapheme-aware counting so a single emoji counts as 1, matching Meta's own behavior on `/threads` create-container calls.

## Failure response

```json theme={"system"}
{
  "error": {
    "code": "preflight_failed",
    "rule": "threads.text.max_graphemes",
    "platform": "threads",
    "message": "Post text is 612 graphemes; Threads allows at most 500."
  }
}
```

## Remediation

Trim the post. Use the same grapheme-aware approach as for Bluesky — see [`bluesky.text.max_graphemes`](/preflight/bluesky-text-max_graphemes) for code.

## Related

* [`threads.text.required`](/preflight/threads-text-required)
* [Platforms / Threads](/platforms/threads)