Loading tools
Loading tools
Loading tool
3 variants side by side, image preview, hex dump fallback.
Base64 is a way to encode binary data as ASCII text so it can travel through email, URLs, JSON, or anywhere that only handles printable characters. This tool encodes text or files to Base64 (standard, URL-safe, and MIME variants side by side) and decodes Base64 back to text or binary, with image preview for image bytes and a hex dump fallback for unrecognizable binary.
Most online encoders only do standard Base64. We show all three variants at once, sniff decoded bytes for image magic numbers (PNG, JPEG, GIF, WebP, BMP, SVG, PDF) so you get a live preview, and render a hex dump when text decoding fails. Everything runs in your browser. Your data never leaves the page.
Most tools only show standard. Need URL-safe for a JWT? Need MIME wrapped? Both visible at once.
Pasted a long Base64 string from CSS? See it as an image immediately. No copy-paste to a separate viewer.
Decoder works on binary too. Hex view with ASCII column lets you debug encoded protocols, file headers, anything binary.
Sensitive tokens, signed payloads, image data, leaked credentials -none of it leaves your laptop.
| Feature | Molixa | base64encode.org | base64decode.org | DenCode |
|---|---|---|---|---|
| 3 variants side by side | Yes | Standard only | Standard only | Yes |
| Image preview on decode | Yes | No | No | No |
| Hex dump fallback | Yes | No | No | No |
| File encode (drop file) | Yes | Yes (paid?) | No | Yes |
| Auto-detect variant | Yes | No | No | No |
| Free, no signup, no ads | Yes | Ads | Ads | Free |
| Browser-only | Yes | Server-side | Server-side | Yes |
Yes. Unlimited use, no signup, no daily cap. Encoding and decoding run in your browser. Base64encode.org is free but ad-supported and ships your data to a server; we don't.
Standard Base64 uses A-Z, a-z, 0-9, +, /, and = padding. URL-safe (RFC 4648 §5) replaces + with - and / with _ so the result fits in URLs and JWT tokens without percent-encoding. Padding (=) is also usually dropped. We show both side-by-side.
Yes. Drop any file (image, PDF, archive) up to about 50MB and the tool reads its bytes via the FileReader API and produces the Base64 string. For images, the decode side will show a live preview.
When you decode Base64 that came from an image, we sniff the magic bytes (89 50 4E 47 for PNG, FF D8 FF for JPEG, etc.) and render it as a data: URL. Useful for debugging email attachments or data: URIs from CSS.
When decoded bytes aren't valid text (e.g. a zip or executable), the text preview shows replacement characters. The hex dump shows the actual byte values in 16-byte rows with offset and ASCII columns, like Unix's xxd. First 256 bytes shown for readability.
Up to about 50MB depending on browser memory. The btoa/atob primitives are fast but Chrome / Firefox cap the string length around 256MB. For genuinely large files, command-line base64 is faster, but we handle most use cases comfortably.
UTF-8 (default, modern web), Latin-1 (single-byte legacy), UTF-16 LE (Windows files). Toggle on the encode side; the decode side auto-falls-back. Most inputs are UTF-8 these days.
No. The encoder runs btoa() on UTF-8-encoded bytes. The decoder runs atob() on the input. Both are browser-native. There's no API call, no log, no telemetry. Even your file uploads stay local via FileReader.
Supported. Some old email standards wrap Base64 at 76 characters. We render that variant too. The decoder strips any whitespace before decoding so you can paste any of the three formats.
Yes for the visible parts. JWTs are three Base64URL-encoded strings joined by dots (header.payload.signature). Paste the whole token and we decode each segment. Note: signatures verify the contents but aren't human-readable; the header and payload are JSON.
3 variants, image preview, hex dump, browser-only. Free unlimited.
Open the Base64 codecThe Base64 Encoder/Decoder page is built, reviewed, and maintained by the Molixa team. We use the tool we ship and update the docs when the behavior changes.