Base64 turns binary data into plain ASCII text. You'll see it in JWT tokens, email attachments, data URIs, API payloads, and config files. When you need to encode or decode fast, a browser tool beats writing a one-off script.
What is Base64?
Base64 maps every 3 bytes of input to 4 printable characters using A–Z, a–z, 0–9, +, and /. Padding = is added when input length isn't a multiple of 3.
Common uses:
- Embedding small images in HTML/CSS (
data:image/png;base64,...) - Encoding credentials in HTTP Basic Auth headers
- Serializing binary blobs in JSON APIs
- Decoding JWT header and payload segments (Base64URL variant)
Encode and decode in your browser
The VyomaStack Base64 Encoder runs 100% locally:
1. Paste text into the input field 2. Click Encode to get Base64 output 3. Paste Base64 into the input and click Decode to reverse it 4. Use Swap to move output back to input for chained operations
Full UTF-8 support — emoji, CJK characters, and accented text encode correctly.
Base64 vs Base64URL
| Standard Base64 | Base64URL (JWT, URLs) |
Uses + and / | Uses - and _ |
Padding = | Often strips padding |
| Email, MIME | JSON Web Tokens, filenames |
JWT decoding uses Base64URL. For standard Base64 text, use the encoder tool directly.
When developers reach for Base64
- Quick-check an API response that returns encoded content
- Decode a config value from Kubernetes secrets or CI variables
- Encode a small JSON snippet for a query parameter (prefer proper URL encoding for full URLs)
- Debug MIME multipart email bodies
Security notes
- Base64 is encoding, not encryption — anyone can decode it
- Never treat Base64 as a way to hide passwords or API keys
- VyomaStack processes locally, but still avoid pasting production secrets into any online tool when possible
Base64 tool vs command line
bash # macOS / Linux echo -n "hello" | base64 echo "aGVsbG8=" | base64 -d
The browser tool is faster for one-off debugging — no terminal, no flags, copy button included.
Related tools
- JWT Decoder — tokens use Base64URL-encoded parts
- URL Encoder — percent-encoding for query strings
- Hash Generator — checksums and fingerprints
Try it free
Encode and decode Base64 instantly — no account, no server upload.