🔐 Free · Instant · No Signup

Encode. Decode. Nothing leaves your browser.

Convert text to and from Base64 or URL-safe format instantly — private by design, since nothing is ever uploaded.

2Modes: B64 & URL
2Directions: En/Decode
LiveAuto-Convert
0Signup

EkZapp's free Base64 & URL Encoder/Decoder converts text between plain form and Base64 or URL-encoded format instantly as you type — no signup, and nothing you enter ever leaves your browser. Choose the Base64 or URL tab, pick Encode or Decode, and start typing; the output updates live with every keystroke.

A common situation this solves: an API returns a Base64-encoded string, a JWT token, or an image data URI, and you need to see what it actually contains. Rather than writing a script or opening a code console, you paste it here, switch to Decode mode, and read the plain result instantly — or go the other direction, encoding a string before embedding it in a config file or URL parameter.

Everything runs client-side using your browser's built-in btoa/atob and encodeURIComponent/decodeURIComponent functions. Nothing you type is uploaded to a server — conversion happens the instant you stop typing, with no delay and no risk of sensitive strings being logged anywhere.

The Swap Result to Input button is built specifically for verification — after encoding something, click it to instantly move the result back into the input box with the mode flipped to Decode, confirming the round trip gives back exactly what you started with.

Why this one

Built for speed and privacy

Live Auto-Convert

The output updates as you type — no button required for the conversion itself, though one's there if you prefer it.

Nothing Ever Uploaded

Encoding and decoding both run using your browser's own JavaScript engine — no network request is made at all.

One-Click Round-Trip Check

Swap Result to Input flips the mode and reloads the output, so you can instantly verify a decode matches the original.

Made for

Wherever encoding comes up

💻

API Developers

Decode a Base64 payload, JWT segment, or auth token to inspect its actual content while debugging.

🌐

Web Developers

URL-encode query parameters containing spaces or special characters before building a link.

🖼️

Embedding Images

Convert a small image or icon into a Base64 data URI to embed directly in CSS or HTML without a separate file request.

📧

Email & Attachment Systems

Inspect Base64-encoded attachment content that some email protocols use to transmit binary data as text.

🔧

Config & Env Variables

Encode a secret or config value into Base64 before storing it in an environment variable or CI/CD pipeline.

🧪

QA & Debugging

Quickly decode an encoded string found in logs or network requests to understand what data is actually being sent.

📚

Students Learning Encoding

Experiment with encoding and decoding to understand the difference between Base64 and URL encoding hands-on.

🔗

Sharing Links

URL-encode text containing symbols or non-English characters before appending it as a query parameter in a shared link.

Comparison

EkZapp vs. a browser console script

TaskEkZapp Encoder/DecoderBrowser dev console
Setup required✓ NoneOpen dev tools, type a command
Handles Unicode/emoji safely✓ Built inRequires extra encodeURIComponent wrapping
Round-trip verification✓ One click (Swap)Manual, type it again
Works on mobile✓ YesDev console rarely available
Cost✓ FreeFree, but requires dev familiarity
Guide

How to use the encoder/decoder

1

Choose Base64 or URL

Pick the tab depending on what you want to convert — Base64 for binary/text encoding, URL for query-string-safe text.

2

Select Encode or Decode

Choose whether you're converting plain text into the encoded format, or an encoded string back to plain text.

3

Type or Paste Your Text

The Output box updates automatically as you type — no need to click Convert unless you prefer to trigger it manually.

4

Copy or Verify

Click Copy Output to copy the result, or Swap Result to Input to instantly check that decoding gives back your original text.

Reference

Base64 vs. URL encoding

A

Base64

Re-encodes the entire input into a set of 64 safe ASCII characters (A-Z, a-z, 0-9, +, /) — commonly used for embedding binary data like images or files as text.

B

URL Encoding

Leaves most characters unchanged and replaces only unsafe ones (spaces, &, ?, #, etc.) with a percent sign followed by a hex code — used for safely including text in a URL.

C

When to Use Which

Use URL encoding for anything going into a link or query parameter; use Base64 for binary data, tokens, or when a system specifically expects Base64 input.

Good to know

Encoding is not encryption

It's a common misconception that Base64 hides or protects data — it doesn't. Base64 is a reversible, publicly documented encoding scheme with no key or password involved; anyone who copies a Base64 string can decode it back to the original text in seconds using any of thousands of free tools, including this one. If you've ever seen a password or API key "obfuscated" as a Base64 string in a config file, that's worth flagging — it provides no real protection at all.

The actual purpose of Base64 is representation, not protection: it exists to safely carry binary data (like an image file or a cryptographic signature) through systems that only handle plain text, such as email, JSON, or XML. It solves a compatibility problem, not a security problem — the data is exactly as visible after encoding as before, just represented using a different, text-safe character set.

For anything that actually needs to stay confidential — passwords, API secrets, personal data — proper encryption (with a real key that only authorized parties hold) is the correct tool, not Base64 or URL encoding. This tool is well suited for its intended purpose of format conversion and inspection, but it should never be treated as a way to secure sensitive information.

FAQ

Frequently asked questions

What is Base64 encoding used for?
Base64 encoding converts binary data or text into ASCII characters, commonly used to embed images in HTML/CSS, send data in JSON/XML APIs, or safely transmit data over text-based protocols like email.
Why do I need to URL encode a string?
URL encoding (percent-encoding) converts special characters like spaces, &, and ? into a safe format for URLs, preventing broken links and query string errors.
Is my data safe using this tool?
Yes, all encoding and decoding happens locally in your browser using JavaScript — nothing is ever uploaded to a server.
What happens if I try to decode invalid Base64?
The tool shows an error message letting you know the input isn't valid Base64, so you can double-check your text before converting.
Is Base64 the same as encryption?
No. Base64 is an encoding scheme, not encryption — anyone can decode it back to the original text instantly, so it should never be used to protect sensitive information.
Why does Base64 output look longer than the original text?
Base64 represents every 3 bytes of input as 4 output characters, which increases the size by roughly 33% — a necessary tradeoff for safely representing binary data as plain text.
What's the difference between URL encoding and Base64 encoding?
URL encoding replaces specific unsafe characters with percent-escaped codes while leaving most text unchanged; Base64 re-encodes the entire input into a completely different character set, regardless of what the original characters were.
Can I use this tool to encode emojis or non-English text?
Yes, both Base64 and URL encoding here handle Unicode text correctly, including emojis and non-Latin scripts, thanks to the UTF-8 conversion step built into the encoding process.
What does the "Swap Result to Input" button do?
It moves the current output into the input box and switches the mode (encode to decode, or decode to encode), which is a quick way to verify a round-trip conversion gives back the original text.
Why would I URL encode something that's going into JSON, not a URL?
You generally wouldn't — URL encoding is specifically for characters unsafe in a URL; JSON has its own string escaping rules, so this tool's URL mode is intended for query strings and URL parameters, not JSON payloads.
Does this tool work offline?
Once the page has loaded, encoding and decoding run entirely in your browser's JavaScript engine, so the tool continues to function even without an active internet connection.
Is this tool free?
Yes, completely free. No signup required, and there's no limit on how many times you can use it.
About this tool

Why it's free, and how it stays that way

The Base64 & URL Encoder is one of more than fifty free tools on EkZapp, sitting alongside a JSON Formatter, Color Picker, and other developer utilities. Because encoding and decoding run entirely as JavaScript in your browser using built-in functions, there's no server processing cost involved — the page loads once, and every conversion afterward is essentially free to run, which is exactly why the tool carries no usage limit or paywall.

This kind of utility tends to get opened for a quick check in the middle of debugging something else — a token decoded, a string encoded, then straight back to the actual code. That's part of why the page stays a single screen with no extra steps: pick a tab and mode, type or paste, and read the result.

It also means there's very little that can go wrong. There's no account to lose access to, no history of past conversions saved anywhere, and no settings menu to configure before the tool does what you need. Every visit starts from the same default state, which keeps the tool predictable whether you use it once a year or several times a day.