Base64 Converter

What Is Base64 Encoding?

Base64 is a binary-to-text encoding scheme that represents arbitrary binary data using only 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). It was designed to allow binary data — like images, files, or cryptographic keys — to be safely transmitted in text-based protocols that can't handle raw binary, such as email (MIME), HTTP headers, and JSON payloads.

A Base64 string is about 33% larger than the original binary data but is universally safe to pass through any text channel without corruption. Decoding reverses the process, recovering the original binary exactly.

Common Use Cases

Embedding Images in HTML/CSS

Instead of a separate HTTP request for a small icon, you can embed it as a Base64 data URI directly in HTML or CSS: src="data:image/png;base64,iVBOR...". This reduces HTTP requests but increases file size — suitable for small icons, not large photos.

API Payloads

REST APIs that accept file uploads via JSON encode binary file content as Base64 strings within the JSON body. Decode incoming Base64 strings to verify the content type and structure.

Authentication Tokens

Basic Authentication headers use Base64-encoded credentials. JWT tokens use Base64url (a URL-safe variant) to encode their header and payload. Decode JWT payloads instantly to inspect claims without a separate tool.

Cryptographic Keys & Certificates

PEM-format certificates and private keys are Base64-encoded DER structures. Decode them to inspect the structure or extract specific fields for debugging TLS issues.

Privacy Note

If you're decoding authentication tokens, API credentials, or private keys, using an online tool that sends your data to a server is a serious security risk. Edita's Base64 Converter runs entirely in your browser — nothing is transmitted.

Related Tools

Working with binary data? Also try the Binary Converter for decimal/hex/binary conversions, or the JSON Formatter to parse decoded API payloads.