# File upload guide

Use the File Upload API to securely send files to Stripe, such as dispute evidence, identification documents, and so on.

We support the ability to upload files to Stripe directly from the browser. Write JavaScript that calls the appropriate endpoint and includes your *publishable* API key. If you need to generate a *file link* for an uploaded file, you need to call the upload API from your integration’s back end instead, following [best practices](https://docs.stripe.com/keys-best-practices.md) by using a [restricted API key](https://docs.stripe.com/keys/restricted-api-keys.md) that has **Files: Write** permission or a well-protected secret API key.

When you upload a file to Stripe using the API, it returns a file token and other information about the file. You can then use the token in other API calls. This guide describes this process.

## Upload a file

To upload a file, send a `multipart/form-data` request to **https://files.stripe.com/v1/files**. The subdomain **files.stripe.com** is different than most Stripe API endpoints. Specify a `purpose` and a `file` in the request. The following example uploads a file located at **/path/to/a/file.jpg** on your local file system with the purpose `dispute_evidence`:

#### curl

```bash
curl https://files.stripe.com/v1/files \
  -u <<YOUR_SECRET_KEY>>: \
  -F "file"="@/path/to/a/file.jpg" \
  -F "purpose"="dispute_evidence"
```

The following example uploads a file using our Android SDK with the purpose `dispute_evidence`:

#### Kotlin

```kotlin
class CheckoutActivity : AppCompatActivity() {
    private val stripe: Stripe by lazy {
        Stripe(this, "<<YOUR_PUBLISHABLE_KEY>>")
    }

    private fun uploadFile(file: File) {
        stripe.createFile(
            StripeFileParams(
                file,
                StripeFilePurpose.DisputeEvidence
            ),
            callback = object : ApiResultCallback<StripeFile> {
                override fun onSuccess(result: StripeFile) {
                    // File upload succeeded
                }

                override fun onError(e: Exception) {
                    // File upload failed
                }

            }
        )
    }
}
```

There are [several valid purpose](https://docs.stripe.com/api.md#create_file-purpose) values, each with file format and size requirements.

> `identity_document` images also need to be smaller than 8,000px by 8,000px.

The MIME type of the file you want to upload must correspond to its file format.

> Any Microsoft Office documents containing VBA macros will be rejected because of security concerns.

A successful request returns a [File](https://docs.stripe.com/api/files/object.md) object.

## Retrieving a File API resource

To retrieve the API resource for a file, make a GET request to the **/v1/files** endpoint of the **files.stripe.com** subdomain providing the file upload ID:

#### curl

```bash
curl https://files.stripe.com/v1/files/{{FILE_ID}} \
  -u <<YOUR_SECRET_KEY>>
```

When using restricted API keys, you must receive prior access to the `Files` resource.

## Download the file contents 

If the file purpose allows downloading the file contents, then the [file](https://docs.stripe.com/api/files/object.md) includes a non-null `url` field indicating how to access the contents. This url requires authentication with your Stripe API keys.

```bash
curl https://files.stripe.com/v1/files/{{FILE_ID}}/contents
  -u <<YOUR_SECRET_KEY>>
```

If you want unauthenticated access to a file whose purpose allows downloading, then you can produce anonymous download links by creating a [file_link](https://docs.stripe.com/api.md#file_links).

#### curl

```bash
curl https://api.stripe.com/v1/file_links \
  -u <<YOUR_SECRET_KEY>>
  -d file={{FILE_ID}}
```

The file_link resource has a `url` field that allows unauthenticated access to the contents of the file.

## Using a file 

After you upload a file, you can use the file upload ID in other API requests. For example, to attach an uploaded file to a particular dispute as evidence:

#### curl

```bash
curl https://api.stripe.com/v1/disputes/{{DISPUTE_ID}}
  -u <<YOUR_SECRET_KEY>>
  -d "evidence[receipt]"={{FILE_ID}}
```

You can only use an uploaded file in a single API request.

## Handle Upload Errors 

When you use the File API to upload a PDF document, we run it through a series of checks to validate that it’s correctly formatted and meets PDF specifications. We return an error for uploads that fail any of our checks.

Try the following to fix errors that we detect:

- Remove annotations or additional media you added to the document.
- If you can’t remove your annotations or media, or if you combined several PDFs into one, try using your computer’s “Print to PDF” function to create a fresh document.
  - [Print to PDF with macOS](https://support.apple.com/guide/mac-help/save-a-document-as-a-pdf-on-mac-mchlp1531/mac)
  - [Print to PDF with Adobe Acrobat](https://helpx.adobe.com/acrobat/using/print-to-pdf.html)