Base 64 encoding and decoding

The calculators encode string to base64 string and decode back to original string. Special characters (+/) , generally produced by base64 algorithm, can be replaced by the data provided in additional parameter.

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To convert a string in base64 format and back to original text you may use the calculators below.

PLANETCALC, Base 64 encoder

Base 64 encoder

Text to be base64 encoded


Base64 encoding algorithm converts input string to characters sequence, which has digits from 0 to 9, letters from a to z, capital letters from A to Z and two special symbols: + (plus) and / (slash). Latter two symbols cannot be used in web URL. You may change these two symbols to something else by passing desired replacement in the Special symbols replace parameter.

PLANETCALC, Base64 decoder

Base64 decoder

Text encoded as base64


The calculator transforms input string in UTF8 characters array and then perform encoding as described in Mozilla Developer Network article