Encoding Tools That Don't Phone Home

Base64 images, decode JWTs, escape HTML entities —all in your browser. Your data is never uploaded to a server.

Encoding tools are dangerous when done server-side —you're literally pasting sensitive data into a stranger's server. These tools run entirely in your browser. Decode JWTs without sending tokens over the wire. Encode images to Base64 without uploading them.

Base64 Encode / Decode

Encode text, files, or images to Base64. Decode Base64 strings back to original. Supports UTF-8, binary-safe, and Data URL generation. Drag-and-drop image to Base64.

Open Base64 Tool →

Base64 Image Encoder

Convert any image (PNG, JPG, SVG, WebP) to a Base64 Data URL. Embed directly in HTML/CSS without external files. Shows file size inflation ratio (Base64 adds ~33%).

Encode Image →Base64 →

JWT Decoder

Decode JWT header, payload, and signature. Shows expiration time in human-readable format with time-until-expiry countdown. Flags expired tokens. No secret key required for decode.

Decode JWT →

URL Encode / Decode

Encode query parameters safely for URLs. Decode percent-encoded strings back to readable text. Handles full URL vs. component encoding (encodeURI vs. encodeURIComponent).

Encode / Decode URL →

HTML Entity Encoder

Convert special characters to HTML entities (< →`&lt;`). Decode entities back to characters. Supports named, decimal, and hex entities. Prevents XSS in user-generated content.

Convert Entities →

Unicode Escape / Unescape

Convert text to Unicode escape sequences (\uXXXX) and back. Supports surrogate pairs for emoji and characters beyond BMP. Useful for JavaScript/JSON string literals. Try our URL encoder for percent-encoding needs.

URL Encode/Decode →

URL & Query String Parser

Decompose any URL into protocol, host, port, path, query params (editable table), and hash. Convert between query strings and JSON. Encode/decode individual parameters interactively.

Parse URL →

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