# gt-next: General Translation Next.js SDK: tx
URL: https://generaltranslation.com/en-GB/docs/next/api/strings/tx.mdx
---
title: tx
description: API reference for the tx string translation function
---

## Overview

The `tx` function is a server-side function for translating strings.

```jsx
await tx('Hello, world!'); // returns 'Hola, mundo!'
```

<Callout>
  **Runtime Translation:**
  `tx` translations occur at runtime.
  This means translation happens live, so you can translate content available at runtime.
</Callout>


## Reference

### Parameters

<TypeTable
  type={{
  "content": {
      type: 'string',
      optional: false,
  },
  "options?": {
      type: 'RuntimeTranslationOptions',
      optional: true,
      default: '{}',
  },
}}
/>

| Name      | Description                                                                                                                                     |
| --------- | ----------------------------------------------------------------------------------------------------------------------------------------------- |
| `content` | The string to be translated.                                                                                                                    |
| `options` | Translation options for customising the behaviour of `tx`. See [`RuntimeTranslationOptions`](/docs/next/api/types/runtime-translation-options). |

### Returns

A promise that resolves to a string containing the translated content, or the original content if no translation is required.

***

## Behaviour

The `tx` function translates strings at runtime.
This means translations are performed live, so you can translate content that is only known at runtime.
The trade-off is that there is a delay while an on-demand translation loads, which is significantly slower.

Our advice is to translate everything you can at build time using [`getGT`](/docs/next/api/strings/use-gt), [`useGT`](/docs/next/api/strings/use-gt), or [`<T>`](/docs/next/api/components/t),
and only use on-demand translations, like `tx` and [`<Tx>`](/docs/next/api/components/tx), when necessary.

Make sure to follow the [deployment guide here](/docs/next/tutorials/quickdeploy).

***

## Example

### Basic usage

You can use `tx` to translate strings.

```javascript title="src/components/translateGreeting.jsx" copy
import { tx } from 'gt-next/server';

export default async function translateGreeting() {
    return await tx("Hello, world!"); // [!code highlight]
}
```


### Adding context

You can customise the translation by providing context to take into account during translation.

```javascript title="TranslateWithOptions.jsx" copy
import { tx } from 'gt-next/server';

export default async function TranslateWithOptions() {
    return await tx("Hello, world!", {
      $context: 'Translate informally' // [!code highlight]
    });
}
```


### Using variables

To pass values to your string, you must (1) assign an identifier and (2) reference the identifier in the object you pass in.

```jsx title="translateWithVariables.js" copy
// [!code word:price]
import { tx } from 'gt-next/server';

export default async function translateWithVariables() {
  return await tx("The cost is {price, number, ::currency/USD}", {
    price: 29.99,
  });
}
```


### Specifying a locale

You can specify which locale to use for the translation.
By default, the locale is set to the user&#39;s preferred language.

```jsx title="translateWithLocale.js" copy
import { tx } from 'gt-next/server';

export default async function translateWithLocale() {
    return await tx("Hello, world!", { $locale: 'fr' }); // [!code highlight]
}
```

***


## Notes

* `tx` is exclusively for server-side use and cannot be used in client-side components.
* Translations with `tx` occur at runtime, meaning they are translated live. This is significantly slower than translations at build time.

## Next steps

* See [`useGT`](/docs/next/api/strings/use-gt) and [`getGT`](/docs/next/api/strings/get-gt) for translating strings before deployment.
* For translating JSX, see [`<T>`](/docs/next/api/components/t) and [`<Tx>`](/docs/next/api/components/tx).
* See [`RuntimeTranslationOptions`](/docs/next/api/types/runtime-translation-options) for more information on customising translations.