---
title: Variables and Secrets
description: Variables and secrets are bound as follows:
image: https://developers.cloudflare.com/dev-products-preview.png
---

> Documentation Index  
> Fetch the complete documentation index at: https://developers.cloudflare.com/workers/llms.txt  
> Use this file to discover all available pages before exploring further. 

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# Variables and Secrets

## Bindings

Variables and secrets are bound as follows:

JavaScript

```
const mf = new Miniflare({  bindings: {    KEY1: "value1",    KEY2: "value2",  },});
```

## Text and Data Blobs

Text and data blobs can be loaded from files. File contents will be read and bound as `string`s and `ArrayBuffer`s respectively.

JavaScript

```
const mf = new Miniflare({  textBlobBindings: { TEXT: "text.txt" },  dataBlobBindings: { DATA: "data.bin" },});
```

## Globals

Injecting arbitrary globals is not supported by [workerd ↗](https://github.com/cloudflare/workerd). If you're using a service Worker, bindings will be injected as globals, but these must be JSON-serializable.

```json
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```