What is Magic number?

A magic number is a fixed byte sequence at the start of a file that identifies its format, letting software detect a file’s type from its contents rather than its extension.

2 tools that work with Magic number

Files never leave your browser.

Encoders & Decoders1

Base64 to File ConverterDecode Base64, a data URI or hex back into a downloadable file, with the type detected automatically.

Browser & Device1

File Type IdentifierIdentify any file from its magic bytes, and see whether the extension is telling the truth.

Related terms

Terms that appear alongside Magic number on the same tools.

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