Base64 Encode / Decode
Convert text to and from Base64 encoding. Fully client-side.
What is the Base64 Encode / Decode?
The Base64 Encode / Decode tool converts arbitrary text or binary data into a compact ASCII string and back again. Base64 is the format used to embed images in emails, credentials in HTTP headers and binary blobs inside JSON payloads — situations where plain bytes cannot survive.
Developers use Base64 dozens of times a day: encoding an OAuth client secret for Basic auth, decoding a JWT payload, embedding a small PNG in CSS, or moving binary data through a text-only transport. This tool handles both directions with a click.
Encoding and decoding run in your browser. Secrets and credentials never travel to a server, which is essential for anyone working with production tokens.
How to use the Base64 Encode / Decode
- 1Paste the text you want to encode or the Base64 string you want to decode.
- 2Pick a mode: "Encode" (text → Base64) or "Decode" (Base64 → text).
- 3Choose the character encoding — UTF-8 for most modern applications.
- 4Click the action button and read the result.
- 5Copy the output to your clipboard with a single click.
Key features
- Two-way encoding and decoding
- UTF-8 support for non-Latin characters
- Optional URL-safe Base64 (- and _ instead of + and /)
- Handles multi-line input
- One-click copy and swap
- Fully offline execution
Examples
HTTP Basic auth
user:supersecretdXNlcjpzdXBlcnNlY3JldA==Decode a JWT payload
Copy the middle part of a JWT and decode it to reveal the JSON claims (header, payload).
Inline image in CSS
Encode a small PNG into a data URI so you can drop it into a stylesheet.
Why use this tool
- Instantly turns credentials into HTTP-friendly strings
- Great for debugging tokens without a full library
- Works offline — safe for production secrets
- Handles Unicode correctly
- Free and unlimited
Common use cases
- Preparing Basic authentication headers
- Decoding JWT payloads while debugging
- Embedding images in emails and CSS
- Sending binary data inside JSON payloads
- Encoding small blobs for URL parameters
- Teaching students how encoding schemes work
Frequently asked questions
Is Base64 encryption?
No. It is an encoding scheme, not encryption. Anyone can decode it — never rely on it to hide secrets.
Why is my decoded text garbled?
The input probably was not text or used a different character encoding. Try switching between UTF-8 and Latin-1.
Does the tool support URL-safe Base64?
Yes — enable the toggle to swap + and / for - and _.
Is my data uploaded?
No — everything is encoded and decoded locally.
Can I encode binary files?
Use our Image to Base64 tool for images. Support for arbitrary file uploads is on the roadmap.