Encode text to Base64 or decode Base64 back to text, with full Unicode support — entirely in your browser. Nothing you enter here is ever sent to Brekzy.
Affects Encode output only. Decoding always accepts either standard or URL-safe Base64 automatically, so you don't need to toggle this to decode a URL-safe string.
Base64 is a way of representing binary data, or any sequence of bytes, using only 64 printable characters: the letters A-Z and a-z, the digits 0-9, and two extra symbols, usually + and /, with = used for padding at the end. It was designed for systems that only reliably handle plain text, so images, files, or arbitrary byte sequences can travel through email, JSON, URLs, or config files without getting mangled along the way.
Base64 and encryption solve different problems. Encoding re-represents the same data in a different, more transportable format; it doesn't hide anything. Base64's 64-character alphabet and conversion rules are fixed and public, so decoding a Base64 string back to its original bytes takes one line of code in nearly any programming language, no key or password required. Encryption, by contrast, is specifically designed to keep data unreadable to anyone without the correct key. If you need to keep information confidential, Base64 is the wrong tool for the job — it only changes how data looks, not who can read it.
Base64 encoding takes the input's raw bytes in groups of 3 (24 bits) and repacks them into 4 groups of 6 bits each. Since 6 bits can represent 64 possible values, each 6-bit group maps directly to one character in the standard alphabet (A-Z, a-z, 0-9, +, /). When the input's length isn't a clean multiple of 3 bytes, one or two = padding characters are added at the end to keep the output length a multiple of 4. The net effect: encoded output is always about 33% larger than the original data, and it's built entirely from the fixed alphabet above, so it's safe to place in contexts that don't tolerate arbitrary binary bytes.
Base64 shows up anywhere binary data needs to travel through a text-only channel:
These two are easy to mix up because both turn input into ASCII-safe text, but they solve different problems. Base64 re-represents arbitrary binary data, not just text, as a fixed alphabet of 64 printable characters; it has nothing to do with URLs specifically, and most of the original data is unrecognizable in the output. URL encoding (percent-encoding) instead starts from text and only escapes the specific characters that aren't safe to place literally inside a URL, such as spaces or &, leaving everything else untouched. Use the URL-safe checkbox above when Base64 output needs to travel inside a URL, filename, or cookie value without further escaping. If your input is a URL or a URL component rather than binary data, use the URL Encoder & Decoder instead.
No. Base64 is an encoding format, not encryption. It re-represents bytes as text using a fixed, publicly known 64-character alphabet, and anyone can decode it back with a single line of code. It provides no confidentiality and should never be used to protect sensitive data.
Yes. This tool converts text to its UTF-8 byte sequence before encoding, so emoji, accented Latin characters, and scripts like Japanese, Russian, or Arabic all encode and decode correctly, round-tripping back to the exact original text.
No. Every conversion happens locally in your browser using JavaScript. Nothing you type here is sent to Brekzy or stored anywhere on our end.
Yes. Switch to Decode mode, paste in a Base64 string, and the tool converts it back to its original text, provided the input is valid Base64.
You will see a clear error message explaining that the input doesn't look like valid Base64, usually caused by invalid characters or incorrect padding, rather than a broken page or a silently wrong result.
Standard Base64 uses "+" and "/" and pads with "=", all of which need extra escaping inside URLs, filenames, or cookie values. Turning on the URL-safe checkbox before encoding swaps those for "-" and "_" and drops the padding, so the result can be dropped straight into a URL or filename. You never need to toggle it just to decode -- this tool accepts both standard and URL-safe Base64 automatically.
They solve different problems. Base64 re-represents arbitrary binary data as text using a fixed 64-character alphabet, with no connection to URLs specifically. URL (percent) encoding instead takes text that may already be readable and escapes only the specific characters that aren't safe to place literally inside a URL, such as spaces or "&". See the comparison section above for more detail.
Yes, completely free, with no account, sign-up, or usage limit.
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