Base64 Encoder/Decoder
Encode text to Base64 or decode Base64 back to plain text instantly. Supports UTF-8 and one-click copy.
Our free online Base64 Encoder/Decoder converts plain text to Base64 and Base64 back to plain text in one click. Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters (A-Z,… Paste or type your input above; results update immediately. The tool runs in your browser and we don't store your data.
About This Calculator
Our free online Base64 Encoder/Decoder converts plain text to Base64 and Base64 back to plain text in one click. Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters (A-Z, a-z, 0-9, +, /), making it safe to embed in HTML, CSS, JSON, XML, URLs, and email. This tool fully supports UTF-8 characters including emojis, accented letters, and non-Latin scripts. Use it to create data URIs for images, encode API authentication credentials, prepare data for embedding in markup, or decode Base64 strings you received from an API or log file.
How It Works
Paste your content into the input panel, then click Encode or Decode. When encoding, the tool converts each character to its UTF-8 byte representation and then maps every 3 bytes to 4 Base64 characters using the standard alphabet (A-Z, a-z, 0-9, +, /), padding with = signs if needed. When decoding, it reverses the process to recover the original text. The result appears in the output panel and can be copied to your clipboard with one click. All processing runs entirely in your browser — nothing is uploaded to a server.
How to Use
- Enter your values in the calculator fields above
- Click the calculate button or let the calculator auto-update
- Review your results instantly
- Adjust values as needed to see different scenarios
Frequently Asked Questions
What is Base64 encoding?
Base64 is a way to represent binary data as plain ASCII text. It takes every 3 bytes of input and maps them to 4 characters from the Base64 alphabet (A-Z, a-z, 0-9, +, /). The result is about 33% larger than the original, but it can safely travel through systems that only handle text, such as email (MIME), JSON, XML, or HTML attributes.
Is Base64 the same as encryption?
No. Base64 is an encoding, not encryption. It is fully reversible by anyone without a key. Never use Base64 to protect passwords, tokens, or sensitive data. For security, use proper encryption algorithms like AES or TLS. Base64 is for data transport, not data protection.
What are common uses for Base64?
Developers use Base64 to embed small images in CSS or HTML as data URIs (data:image/png;base64,...), send binary file attachments in email (MIME encoding), include credentials in HTTP Basic Authentication headers, store binary blobs inside JSON or XML payloads, and transmit data through systems that only support printable ASCII characters.
Does this tool handle special characters and emojis?
Yes. The encoder fully supports UTF-8 input, which means accented characters (e.g., cafe), non-Latin scripts (e.g., Chinese, Arabic, Cyrillic), and emojis all encode and decode correctly. The tool handles the multi-byte UTF-8 sequences automatically.
Why is my Base64 output longer than the input?
Base64 maps every 3 input bytes to 4 output characters, so the encoded string is always approximately 33% larger. This is a trade-off for safe text-only transmission. If size is a concern, compress your data (e.g., with gzip) before encoding.
Is my data private?
Yes. All encoding and decoding runs locally in your browser using JavaScript. Your input is never sent to any server. This makes the tool safe for working with API keys, credentials, and any other data you need to encode or decode.
Why Use Our Free Base64 Encoder/Decoder Online?
Our Base64 Encoder/Decoder runs in the browser so you can format, convert, or generate without sending data to our servers. No account needed—paste or type, get your result. We offer more dev tools (JSON, Base64, JWT, UUID, timestamps, and more) in the list below.