Free tools
Base64 Decode
Free online Base64 decoder — paste a Base64 string and instantly get the decoded text output.
Decoded result
Base64 Decode Online
Paste a Base64-encoded string into the field above and click Decode Base64 to instantly see the original text. Everything runs in your browser — nothing is sent to a server.
What Is Base64 Decoding?
Base64 decoding is the reverse of Base64 encoding: it converts a string of printable ASCII characters back into its original binary or text representation. You'll commonly encounter Base64 strings in JWT tokens, data URIs, email headers, and API responses.
Common Uses
- Inspecting the payload of a JWT (JSON Web Token)
- Decoding credentials stored in HTTP Basic Authentication headers
- Reading configuration values or secrets passed as Base64 in environment variables
- Extracting the contents of a
data:URI
How to Use This Tool
- Paste your Base64 string into the input field.
- Click Decode Base64.
- Copy the decoded result with the copy button.
If the input is not valid Base64, an error message will be shown.
Frequently Asked Questions
How do I decode Base64?
Paste any valid Base64-encoded string into the input field. The tool automatically decodes it and shows the original text or binary data. You can decode standard Base64 as well as URL-safe Base64 variants.
What if my Base64 string is invalid?
The tool will show an error if the input isn't valid Base64. Common issues include: non-Base64 characters in the string, incorrect padding (equals signs at the end), or data corruption. Make sure you're copying the complete Base64 string without extra spaces or line breaks.
Can I decode Base64 from images?
If the Base64 string represents an image (you'll see it starts with something like
data:image/png;base64,), you can decode it, but the raw output will be binary data. For viewing images, you can often paste the entire data URI directly into a browser address bar.What's the difference between standard and URL-safe Base64?
Standard Base64 uses
+ and / characters, which aren't URL-safe. URL-safe Base64 replaces these with - and _. This tool handles both formats automatically and will correctly decode either variant.Can I decode binary data?
Yes. Base64 can encode any binary data — images, executables, compressed files, etc. The decoded output will be the original binary content. However, binary data may display as garbled text if shown as a string.
Is this tool secure?
Yes. All decoding happens entirely in your browser. Your Base64 data and decoded content are never sent to any server. For sensitive data, this local processing ensures your information stays private.