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Encode and decode Base64 strings online
Encode text or binary data to Base64 and decode Base64 strings back to plain text. Fast local processing with no data sent to any server. Useful for API authentication headers, email encoding, data URIs, and inspecting JWT token segments.
Frequently Asked Questions
- What is Base64 encoding?
- Base64 is an encoding scheme that represents binary data as ASCII text using 64 printable characters. It is commonly used in HTTP Basic Auth headers, email attachments (MIME), data URIs, and JWT token segments.
- What is the difference between standard Base64 and URL-safe Base64?
- URL-safe Base64 replaces "+" with "-" and "/" with "_", making encoded strings safe to include in URLs and filenames without percent-encoding.
- Can I decode JWT tokens with this tool?
- Yes, but for a dedicated JWT view with claim parsing and expiry detection, use the JWT Decoder tool instead.
- Is the data sent to a server?
- No. All encoding and decoding is performed client-side in your browser using the built-in btoa() and atob() APIs.