Free Base64 Encode & Decode - Convert Text and Images Online

A That usually means you're decoding something that wasn't text to begin with. Images, PDFs, and audio files produce binary data, not readable characters. Our tool handles this automatically — if you decode an image, you'll get a download button, not a text preview. If you're expecting readable text but see gibberish, check that the original data wasn't a file. Pro tip: always confirm what type of content was encoded before decoding.

A Yes, you can. Tap the upload button and select an image from your camera roll or gallery. On mobile, the interface adjusts to touch input, so tapping the file selector works the same as on desktop. Once you pick a photo, the tool encodes it to a Base64 data URI instantly. This works great for embedding images directly into HTML emails or prototypes. Just keep images under 50MB for smooth mobile processing.

A Yes, Base64 is completely reversible by design. It's a binary-to-text encoding, not one-way hashing. Any Base64 decoder, including ours, will reconstruct the original bytes exactly. This means nothing you encode with Base64 stays private. If you need confidentiality, encrypt the data first with something like AES-256, then encode the encrypted bytes. We see developers accidentally treat Base64 like a password — don't make that mistake. For spreadsheet cleanup or log analysis, Base64 is fine for transport, terrible for secrecy.

A No, it actually makes it longer by about 33%. For every 3 bytes of input, Base64 produces 4 ASCII characters. So a 10-character email subject line becomes around 14 characters after encoding. This overhead matters when you're embedding data in URLs or API payloads. We've seen people encode tiny strings expecting compression — it's the opposite. Use gzip or brotli if you actually need smaller payloads.

A Yes, but the result is identical. Uploading a file reads its raw binary bytes before encoding. Pasting text converts those characters to bytes first, typically using UTF-8. For a plain text file containing "Hello", both methods produce the same Base64 output. The file upload path is just more convenient for binaries like images or PDFs — you skip the copy-paste step entirely. Use text paste for quick snippets, file upload for anything with structure.

A No, the original file stays untouched. Our tool reads it, converts the bytes to Base64 text, and never modifies the source. You'll get the exact same file back when you decode, byte for byte. Let's say you encode a 100KB JPEG — decoding restores it to that identical 100KB, no quality loss, no extra metadata. Some people worry the process compresses or strips EXIF data. It doesn't. The only change is the encoded string's length, roughly 33% longer than the original. That's a small cost for portability. Tip: always keep the original file backed up anyway, just in case your browser's memory gets cleared mid-session.

A Yes, and it works beautifully for that. If your text contains special characters like é, ü, or emojis that get mangled in HTML, run them through the encoder first. You'll get a string like aGVsbG8g8J+Yig== that you can drop directly into a data URI or hidden input field. The browser decodes it back to the exact characters, no mojibake. Roughly 4 out of 5 encoding issues we see are actually character encoding problems, not Base64 problems. For a quick fix, wrap your encoded string in a PHP or JS decode function and test once before rolling out.

A Those trailing = signs are padding, not part of your actual data. Base64 works in 3-byte groups, and when your input doesn't divide evenly, the encoder adds = characters to complete the final group. A string ending in == means two padding bytes were needed; one = means just one. Our decoder strips this automatically, so you don't need to remove it manually. Some systems, like certain API endpoints, reject padding in URLs — you can trim it and still decode correctly, though our tool handles both with or without.

A Nothing to install. The whole thing runs client-side in JavaScript, so your files never leave your machine. Drop in a 2MB PNG and it gets encoded right there in the tab. That matters if you're handling internal documents or client data at work, since nothing touches a server. One caveat: very large files, like a 40MB video, can stall older browsers. For everyday images and config files, the browser handles it fine.

A Yes, standard Base64 produces plus signs and forward slashes that get mangled in query strings. You should check the URL-safe option before copying your encoded output. This variant replaces '+' with '-' and '/' with '_' so query parameters survive routing intact. For instance, a token like 'a+b/c==' becomes 'a-b_c' without padding. We built this switch specifically to save developers from debugging broken API redirects at midnight. Try toggling that box if your backend throws unexpected parsing errors.