Encode & Decode Tools Online
Free online tools for Base64, URL, HTML and Gzip encoding and decoding — all running locally in your browser with no data sent to any server.
Encode text, images and files to Base64 or decode Base64 strings. Supports URL-safe Base64, file upload and data URI generation.
Percent-encode URLs, query strings and API parameters or decode them back. Handles special characters, spaces and Unicode.
Escape HTML special characters to named entities for safe display in browsers, emails and templates. Prevents XSS vulnerabilities.
Compress text, JSON and config data with Gzip or decompress Gzip strings. Base64-encoded output for easy copying.
About These Encoding Tools
Encoding converts data from one format to another for safe transmission or storage. Base64 encodes binary data as text, URL encoding makes strings safe for use in URLs, HTML encoding prevents special characters from being interpreted as markup, and Gzip reduces data size for faster transfer.
All tools run entirely in your browser — no uploads, no server requests, no tracking. Safe to use with sensitive tokens, credentials and production data.
Frequently Asked Questions
What is Base64 encoding used for?
Base64 encodes binary data (images, files) into ASCII text so it can be safely transmitted in JSON, HTML, or email. Common uses include embedding images as data URIs in CSS and encoding file attachments in APIs.
When do I need to URL-encode a string?
URL encoding is required when passing special characters (spaces, &, =, ?, #) in query string parameters or path segments. Without encoding, these characters break the URL structure.
What is the difference between HTML encoding and escaping?
They refer to the same thing — converting characters like <, >, & and quotes into HTML entities (<, >, &). This prevents browsers from interpreting user input as HTML, which stops XSS attacks.
Is my data safe when using these tools?
Yes. All encoding and decoding happens locally in your browser using JavaScript. No data is uploaded or sent to any server — not even for file uploads in the Base64 tool.
Can I compress JSON with Gzip before sending it as an API response?
Yes. Use the Gzip tool to compress your JSON and see the compression ratio. The output is Base64-encoded so you can copy and use it directly in your code.