Base64 Normalizer
Paste a Base64 string and convert between the standard and URL-safe alphabets, then add correct padding or strip it entirely.
Input
LocalNormalized output
—About Base64 Normalizer
The Base64 Normalizer converts between the standard and URL-safe alphabets and corrects padding. It is for developers reconciling Base64 that came from different systems.
Standard and URL-safe Base64 use different characters, and mismatches cause decoding to fail. Normalising locally aligns the alphabet and padding instantly and privately.
Step by step
- Paste a Base64 string.
- Convert between standard and URL-safe alphabets as needed.
- Add or strip padding to match the target.
- Copy the normalised result.
What it offers
- Standard and URL-safe conversion
- Padding correction
- Instant output — Base64 Normalizer
- Runs locally — Base64 Normalizer
Where it helps
- Aligning a URL-safe token to standard Base64 for decoding
- Preparing standard Base64 for use in a URL
- Fixing padding before decoding
- Reconciling Base64 from two systems
Tips for best results
- Normalise URL-safe Base64 to standard form before decoding with a standard decoder.
- Match padding to the target context, since URL-safe often omits it.
- Confirm which alphabet the source and destination each expect.
Pitfalls to watch for
- Decoding URL-safe Base64 with a standard decoder without normalising first.
- Adding padding where a URL-safe context expects it stripped, or vice versa.
- Assuming both alphabets are interchangeable without conversion.
Why people use it
Alphabet alignment
Switch between standard and URL-safe.
Padding fixes
Add or strip padding as needed.
Prevents failures
Avoids mismatched-alphabet errors.
Private
Normalised on your device.
Common questions
This runs entirely in your browser
No file or text you enter here is uploaded. Encoding and decoding happen on your device using native browser APIs — close the tab and nothing remains on a server.