Base64 Decoder
Decode Base64 strings back to readable text.
About Base64 Decoder
Base64 Decoder is a free online tool. Decode Base64 strings back into readable text to inspect tokens, headers and payloads. It runs entirely in your browser, so there is nothing to install, no account to create and no watermark added to your result.
How to use Base64 Decoder
- Enter or paste your input.
- Press the button to decode.
- Copy the result.
Worked example
Pasting SGVsbG8= returns the text "Hello". If the input has missing padding or characters like - and _, it is probably URL-safe Base64.
Tips for best results
- If decoding fails, check for missing padding (= at the end) or URL-safe characters (- and _).
- Everything runs in your browser, so you can use Base64 Decoder even on a slow connection once the page has loaded.
Limits to keep in mind
- Encoding is not encryption. Anyone can reverse it, so never use it to protect secrets.
Frequently asked questions
More free developer tools
Base64 Encoder
Encode any text to Base64 instantly.
URL Encoder
Percent-encode URLs for safe transmission.
URL Decoder
Decode percent-encoded URLs back to readable text.
HTML Encoder
Escape HTML special characters into entities.
HTML Decoder
Unescape HTML entities back into characters.
MD5 Hash Generator
Generate MD5 hashes from any text.
Related guides
UUIDs Explained: Versions, Collisions and How to Generate Them
What a UUID is, how version 4 and version 7 differ, why collisions are practically impossible and how to use them as database keys.
2 minBase64 Explained: What It Is, Why It Exists and What It Is Not
How Base64 turns bytes into text, why it adds about a third to the size, where you will meet it and why it is not encryption.
2 minMD5 vs SHA-256: Which Hash Should You Use?
Understand what hash functions do, why MD5 and SHA-1 are considered broken for security and which tool to use for checksums and passwords.