Base64 & URL encoder & decoder
Encode and decode Base64 and URL strings both ways, instantly. UTF-8 safe, with URL-safe Base64 and file-to-Base64 — all in your browser, nothing uploaded.
Output appears here…How it works
Pick a mode
Choose Base64 or URL, then Encode or Decode. The conversion runs live as you type.
Convert both ways
Use the swap button to flip input and output, so you can chain or reverse a conversion in one click.
Copy the result
Copy the output, toggle URL-safe Base64, or drop in a file to Base64-encode it.
Base64 and URL encoding explained
Base64turns binary or text data into a set of 64 safe ASCII characters, so it can travel through systems that only handle text — embedding an image in CSS, attaching a file to an email, or packing data into a token. It's important to remember Base64 is encoding, not encryption: anyone can decode it.
URL (percent) encoding escapes characters that have special meaning in a URL — spaces, ampersands, question marks — so query strings and paths stay valid. Both conversions here are UTF-8 aware and run entirely in your browser, making them safe for sensitive payloads.
Frequently asked questions
Is this Base64 tool free and private?+
Yes — completely free, no sign-up, and everything runs in your browser. Your text and files are never uploaded to a server.
What is Base64 encoding?+
Base64 represents binary data using 64 ASCII characters. It's used to embed images in CSS/HTML, send binary in JSON or email, and store data in URLs and tokens. It is encoding, not encryption — it provides no security.
What is URL-safe Base64?+
Standard Base64 uses + and / which have special meaning in URLs. URL-safe Base64 swaps them for - and _ and drops the = padding, so the result can be used safely in query strings, JWTs, and filenames.
What's the difference between encodeURIComponent and encodeURI?+
Component encoding escapes everything that isn't safe in a single URL component — ideal for query-string values. Full-URL encoding leaves structural characters like :, /, ? and & intact, so it's for encoding a whole URL at once.
Does it handle emoji and non-English text?+
Yes. Both encoders are UTF-8 aware, so emoji, accents, and non-Latin scripts encode and decode correctly without mojibake.
More free developer tools
Browser-based, no sign-up. Explore the full Avenra toolset.