Base64 Encoder & Decoder
FREEEncode text to Base64, or decode Base64 back to plain text — instantly, in your browser. Switch between Encode and Decode mode, paste your input, and copy the result with one click. Nothing you enter is uploaded — everything runs locally.
Why We Built This Tool
Encoding and decoding Base64 are two sides of the same task, so switching between two separate tools never made sense. This tool combines both into one interface with a simple mode toggle — encode text to Base64, or decode Base64 back to plain text, without leaving the page.
How to Use It
Choose Encode or Decode mode, paste your input, and click the button. The result appears instantly below, ready to copy with one click. Everything runs locally in your browser — nothing you enter is uploaded or stored.
Common Mistakes to Avoid
Treating Base64 as encryption
Solution:
Base64 is encoding, not encryption. Anyone can decode it instantly, so it provides zero security. Never use it to hide passwords or sensitive data — encrypt that data properly instead.
Forgetting Base64 increases size
Solution:
Encoding grows your data by roughly 33%, since every three bytes become four characters. Keep this in mind when embedding large files as Base64.
Dropping the padding characters when decoding
Solution:
The "=" signs at the end are padding that keeps the length valid. If a copy-pasted string is missing its trailing padding, decoding will fail — make sure you copy the complete string.
Using standard Base64 in a URL
Solution:
Standard Base64 uses "+" and "/", which have special meaning in URLs. For links and query strings, use URL-safe Base64, which replaces them with "-" and "_".
Frequently Asked Questions
Base64 represents any data using 64 safe, printable characters — A–Z, a–z, 0–9, plus "+" and "/". It converts data into a plain-text form that transfers reliably through systems built for text, like email and URLs.
No. Base64 is encoding, easily and instantly reversible by anyone. It offers no confidentiality — use real encryption if you need security.
Base64 expands data by about 33%, since three bytes of input become four characters of output.
No. Encoding and decoding both happen entirely in your browser — nothing you enter is sent to a server or stored.
What Base64 is for
Base64 is a binary-to-text encoding scheme, not encryption. It represents any data using 64 safe, printable characters, making it reliable for embedding binary content in places built for plain text — email attachments, data URLs, JSON payloads, and HTTP headers.
One tool, two directions
This tool combines encoding and decoding in a single interface with a mode toggle, so you never need to remember which page did which — switch modes, paste your input, and get the result instantly.
Why decoding sometimes fails
A "Invalid Base64 input" error usually means the string is missing its trailing padding characters (=) or was truncated during copy-paste. Always copy the complete string.