Text File Encoding Converter

Encode a local binary or text file as plain Base64 or a Base64 Data URL entirely in your browser. The tool reports the original filename, MIME type, input size, encoded payload size, and estimated expansion before allowing you to copy or download the encoded text. It can also decode pasted plain Base64 or a supported Data URL into downloadable bytes, using a filename and MIME hint that you control when metadata is absent. Strict validation rejects malformed padding, unsupported Data URL structures, oversized inputs, and unsafe filename characters. Decoded content is never previewed, inspected, uploaded, or executed. Temporary download URLs are revoked immediately, and conservative limits reduce avoidable memory pressure.

Generate SHA-256, SHA-384, and SHA-512 digests for a local file with the browser's Web Crypto API. You may also select SHA-1 for compatibility, but the interface clearly identifies it as a legacy algorithm that is unsuitable for new security uses. The tool validates that a non-empty file and at least one algorithm are selected, enforces a conservative size limit, and displays the filename, byte size, selected algorithms, and deterministic hexadecimal digests. Each digest can be copied separately. File bytes, names, and hash values remain in the browser and are never uploaded. A matching digest can help compare bytes, but it does not prove safety, authenticity, ownership, or the absence of malicious content.