Base64 Encoder / Decoder – Text & File Support
Encode any text or file to Base64 — or decode a Base64 string back to plain text — all in real time inside your browser. UTF-8 safe with drag-and-drop file support for images, PDFs, and binary files. No server upload, no data left behind.
Text to Encode
Instant Encoding
Convert text or files to Base64 in real time — no server round-trip required.
100% Private
Everything runs locally in your browser. Your data never leaves your device.
File Support
Drag & drop any file to encode it. Supports images, documents, and binary files.
Included Base64 Tools
Text to Base64 Encoder
Type or paste any text and get the Base64-encoded result in real time.
Base64 to Text Decoder
Paste a Base64 string and decode it back to readable plain text instantly with a valid/invalid badge.
File to Base64 Encoder
Drag & drop any file — image, PDF, or binary — to encode it to a Base64 string without uploading.
Download Result
Save the encoded or decoded output as a .txt file with one click.
How to Encode or Decode Base64 Online
Choose Encode or Decode
Click the Encode tab to convert text or a file to Base64, or Decode to reverse a Base64 string back to plain text.
Paste text or upload a file
Type into the input area or drag & drop any file to load it automatically.
Copy the result
The output updates in real time — copy it directly from the output panel.
Download if needed
Click Download to save the encoded or decoded result as a .txt file.
What Is Base64 and Why Is It Used?
Base64 is an encoding scheme that converts binary data into a string of 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). The name comes from the character set size: 64. Base64 was designed to solve one specific problem: many systems that handle text — email protocols, JSON APIs, HTML attributes, XML — cannot safely transmit raw binary data because certain byte values are interpreted as control characters. Base64 removes that problem by representing every byte pattern as a combination of safe printable characters. The tradeoff is size: Base64-encoded data is approximately 33% larger than the original binary. Common uses: embedding images directly in CSS asdata:image/png;base64,... URI strings to avoid an extra HTTP request, encoding JWT tokens (the header and payload are Base64url-encoded), passing binary data in JSON API payloads, and encoding email attachments in MIME format. Base64 is not encryption — it is a reversible encoding that anyone can decode.
Base64 vs Base64url: What Is the Difference?
Standard Base64 uses + and/ as the 63rd and 64th characters, and= for padding. These characters have special meaning in URLs: + encodes as a space,/ is a path separator, and= can break query strings. Base64url is a URL-safe variant that replaces + with- and / with_, and often omits padding. JWTs use Base64url for all three parts (header, payload, signature). If you are decoding a JWT and getting errors, switch to Base64url decoding and remove any trailing= padding. If you are encoding data to embed in a URL query parameter, use Base64url rather than standard Base64 to avoid the need for additional percent-encoding.
Frequently Asked Questions
- Can I encode images and binary files to Base64?
- Yes. Drag and drop any file — images, PDFs, or binary files — into the input area and the tool encodes it to a Base64 string immediately.
- Is this tool UTF-8 safe?
- Yes. ToolMint uses TextEncoder and TextDecoder rather than raw btoa/atob, so multi-byte Unicode characters (including Hindi, Arabic, Chinese, and emoji) are handled correctly without data loss.
- How do I decode a Base64 string?
- Click the Decode tab, paste your Base64 string into the input, and the decoded text appears instantly. A validation badge confirms whether the input is valid Base64.
- Are my files uploaded to a server?
- No. All encoding and decoding happens locally in your browser using Web APIs. No file or text is ever sent to any server.
- What is Base64 used for?
- Base64 is commonly used to embed binary data (images, files) in JSON or HTML, transmit data through APIs that only support text, encode email attachments (MIME), and store binary data in databases that only accept text.
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