Security
Base64 Encoder / Decoder
Runs entirely in your browser · Nothing is sent to our servers
Encode text to Base64 or decode Base64 to text. Supports UTF-8 and URL-safe mode.
Input
Output
How it works
Base64 encodes binary data as ASCII text by grouping every 3 bytes into 4 characters from a 64-character alphabet (A–Z, a–z, 0–9, +, /).
URL-safe mode replaces + with - and / with _, making the output safe for use in URLs and filenames without percent-encoding.
Common uses include data URIs (inline images in HTML/CSS), email attachments (MIME), and JWT tokens which use URL-safe Base64 for header and payload.
All encoding and decoding happens entirely in your browser. Nothing is sent to any server.
How it works▾
Base64 encodes binary data as ASCII text by grouping every 3 bytes into 4 characters from a 64-character alphabet (A–Z, a–z, 0–9, +, /).
URL-safe mode replaces + with - and / with _, making the output safe for use in URLs and filenames without percent-encoding.
Common uses include data URIs (inline images in HTML/CSS), email attachments (MIME), and JWT tokens which use URL-safe Base64 for header and payload.
All encoding and decoding happens entirely in your browser. Nothing is sent to any server.
Frequently asked questions
Encode text into Base64 or decode Base64 back to plain text. Useful for embedding small assets, debugging tokens, and shipping binary-safe payloads through text-only channels.
- What is Base64 encoding for?
- It rewrites arbitrary bytes using only printable ASCII characters, so you can safely paste binary or non-ASCII text into JSON, URLs, emails, and other text-only contexts.
- What is URL-safe Base64?
- Standard Base64 uses + and / which need escaping inside URLs. URL-safe mode swaps them for - and _ so the encoded value can sit in a URL or filename without further encoding.
- Is Base64 encryption?
- No. It's encoding, not encryption — anyone can decode it. Use it for transport, never to hide secrets.
Use with
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