# General Translation Python SDKs: hash_message
URL: https://generaltranslation.com/en-US/docs/python/reference/functions/hash-message.mdx
---

title: hash_message
description: Hash an ICU MessageFormat string for translation lookup in General Translation Python. API reference for hash_message.

---

Hashes an ICU MessageFormat string into the hex key used to look up its translation. This is the same hash [`t`](/docs/python/reference/functions/t) computes internally, so you can use it to build or inspect a translation dictionary.

## Overview [#overview]

Call `hash_message` with a source string and optional keyword-only context, id, and max-chars. It indexes the message's variables, then hashes it with `data_format="ICU"`.

```python
from gt_i18n import hash_message

h = hash_message("Hello, world!")
```

Signature:

```python
hash_message(
    message: str,
    *,
    context: str | None = None,
    id: str | None = None,
    max_chars: int | None = None,
) -> str
```

Import `hash_message` from `gt_i18n`. It is not re-exported by the framework packages.

## How it works [#how-it-works]

- **Index variables.** It first normalizes the message by indexing its variables, so equivalent messages hash the same way.
- **Hash.** It hashes the normalized message together with `context`, `id`, and `max_chars`, matching the JS gt-i18n implementation. Changing any of these produces a different hash.

## Parameters [#parameters]

| Parameter | Description | Type | Optional | Default |
| --- | --- | --- | --- | --- |
| [`message`](#message) | The ICU MessageFormat source string. | `str` | No | — |
| [`context`](#context) | Context string for disambiguation. | `str \| None` | Yes | `None` |
| [`id`](#id) | Explicit message identifier. | `str \| None` | Yes | `None` |
| [`max_chars`](#max-chars) | Maximum character constraint. | `int \| None` | Yes | `None` |

### `message` [#message]

**Type** `str` · **Required**

The ICU MessageFormat source string to hash.

### `context` [#context]

**Type** `str | None` · **Optional** · **Default** `None`

Optional context (the `_context` option in `t`), used to disambiguate identical source text.

### `id` [#id]

**Type** `str | None` · **Optional** · **Default** `None`

Optional explicit message identifier (the `_id` option in `t`).

### `max_chars` [#max-chars]

**Type** `int | None` · **Optional** · **Default** `None`

Optional maximum character constraint (the `_max_chars` option in `t`).

## Returns [#returns]

**Type** `str`

A hex hash string used as the translation lookup key.

## Example [#example]

```python
from gt_i18n import hash_message

# Build a translation dictionary keyed by hash
translations = {
    hash_message("Hello, world!"): "Hola, mundo!",
}
```