Encoding

Base64 File Encoder & Decoder

Turn a file into Base64 or download a Base64 data URI as a file. Processing stays completely on your device.

Browser-local
Private workspaceInput is kept in this tab
0 chars
Ready
Run the tool to see a result.

File bytes are read with the browser FileReader API and are never uploaded.

About this tool

What Base64 File does

Use this tool to inspect, download, or create Base64 file payloads for APIs, CSS data URIs, email attachments, and test fixtures.

Common uses

  • Preview a Base64 image
  • Create a Base64 payload from a local file
  • Recover a file from an API response

Privacy and limitations

File bytes are read with the browser FileReader API and are never uploaded.

Always validate security-sensitive output in the authoritative application or platform.

Frequently asked questions

What file types are supported?

Any file can be encoded. Common image types can also be previewed.

How large can a file be?

The browser can handle many files, but Base64 increases size by roughly one third, so keep files reasonably small.