curl -X POST 'https://api.anthropic.com/v1/files' \
  -H "x-api-key: $ANTHROPIC_API_KEY" \
  -H 'anthropic-version: 2023-06-01' \
  -F 'file=@sample.bin'

# POST /v1/files (Claude API)
Base URL: https://api.anthropic.com
Auth: x-api-key; Anthropic API key; required.
Request formats: multipart/form-data.
Last verified: 2026-10-20

> Upload File

## Critical Gotchas
* Authentication uses the `x-api-key` header and requests also require an `anthropic-version` header.
* The official OpenAPI URL is discovered from the SDK repository manifest and must remain under Anthropic's trusted Stainless storage prefix.

## cURL
curl -X POST 'https://api.anthropic.com/v1/files' \
  -H "x-api-key: $ANTHROPIC_API_KEY" \
  -H 'anthropic-version: 2023-06-01' \
  -F 'file=@sample.bin'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| file | body | string | Yes | The file to upload |
| expires_in_seconds | body | integer | No | Seconds from upload until the file expires and its bytes become permanently u... |

## Response example
{"created_at":"2026-09-03T00:00:00Z","downloadable":false}

---
Need an API key? Get one at https://console.anthropic.com/settings/keys

POST

POST /v1/files — Claude API

Anthropic API key (required); https://api.anthropic.com

Claude API

Upload File

Base URL: https://api.anthropic.com
Auth: x-api-key: <ANTHROPIC_API_KEY>
Last verified: 2026-10-20 · upstream hash matched

Actions Try in browser→

Agents: curl -H "Accept: text/markdown" this URL
→ 197 tokens · Vary: Accept

Critical gotchas

Authentication uses the x-api-key header and requests also require an anthropic-version header.

The official OpenAPI URL is discovered from the SDK repository manifest and must remain under Anthropic's trusted Stainless storage prefix.

cURL

curl -X POST 'https://api.anthropic.com/v1/files' \  -H "x-api-key: $ANTHROPIC_API_KEY" \  -H 'anthropic-version: 2023-06-01' \  -F '[email protected]'

Parameters

Name	In	Type	Required	Description
file	body	string	Yes	The file to upload
expires_in_seconds	body	integer	No	Seconds from upload until the file expires and its bytes become permanently unavailable. Must be between 3600 (one hour) and 7776000 (ninety days).

Response 200 OK

{
  "created_at": "2026-09-03T00:00:00Z",
  "downloadable": false,
  "expires_at": null,
  "filename": "string",
  "id": "string",
  "mime_type": "string",
  "size_bytes": 0,
  "type": "string"
}

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