Encoder / Decoder

Encode and decode URL text, Base64, URL-safe Base64, and HTML entities in your browser.

Key Terms (Click to expand)

URL

Encodes text for a URL query value or path segment, converting characters such as @, spaces, ?, and &.

Base64

Represents UTF-8 text as a compact ASCII string; it is encoding, not encryption.

Base64 URL-safe

A URL-safe Base64 variant that avoids +, /, and padding characters.

HTML entities

Numeric or named entity sequences that HTML can render back into characters.

Tool

Methodology

The encoder/decoder applies deterministic browser-safe transforms based on the selected mode.

  • URL mode encodes text for a URL query value or path segment, not a full URL document.
  • Base64 and URL-safe Base64 encode UTF-8 text bytes and decode them back to text.
  • HTML entity encoding outputs numeric entities and decoding supports numeric plus common named entities.
  • Input is processed locally in your browser.

Worked Example

A concrete example with realistic numbers will be added for this route.

Assumptions and Limitations

  • Encoding is not encryption and should not be treated as security protection.
  • Base64 decoding requires valid Base64 or URL-safe Base64 input for the selected mode.
  • No server-side persistence is used for encoded or decoded text.

FAQ

Which mode should I use for an email address?

Use URL encoding for URL parameters or HTML entities when you need an HTML-renderable encoded form.

Is Base64 encryption?

No. Base64 is reversible encoding and should not be used to hide secrets.

Is my text uploaded to a server?

No. Encoding and decoding run locally in your browser.