Base64 Encoder / Decoder
Encode plain text or decode Base64 strings instantly without sending data to a server. Runs entirely in your browser for secure, offline processing.
Encode any text to Base64 or decode Base64 strings back to plain text instantly with SolveBar's Base64 tool. Supports both standard Base64 and URL-safe Base64 variants — useful for JWT tokens, data URIs, API authentication headers, and email attachments.
What is Base64 and why is it used?
Base64 converts binary data into a text-safe format using 64 ASCII characters. It is used to safely transmit binary data through text-only channels like email, JSON APIs, and HTML data URIs. It is an encoding, not encryption — it provides no security on its own.
Standard vs URL-safe Base64
Standard Base64 uses + and / characters which have special meaning in URLs. URL-safe Base64 replaces + with - and / with _, making it safe to use in URLs and filenames. JWT tokens use URL-safe Base64 without padding characters.
Common use cases
Decoding JWT token payloads to inspect claims, encoding images as data URIs for CSS backgrounds, sending binary data in JSON APIs, Basic Authentication headers (username:password encoded in Base64), and embedding fonts in CSS files.
Frequently Asked Questions
Does Base64 compress data?
No — Base64 increases data size by approximately 33%. It is for compatibility and transport safety, not compression.
Can I decode a JWT token with this?
Yes. A JWT has three Base64-encoded parts separated by dots. Decode the second part (payload) to see the claims. This does not verify the signature.
Is Base64 the same as encryption?
No. Base64 is a reversible encoding that anyone can decode. Never use it to protect sensitive data.