Drop any file - PDF, DOCX, ZIP, MP3, MP4, anything - and get its Base64-encoded representation. Includes the proper MIME type prefix for use as a data URI. Encoding happens locally in your browser using FileReader - the file is never uploaded.
When to use this
Use when: embedding small file attachments in JSON / XML / GraphQL APIs, generating self-contained HTML emails with embedded PDFs, prepping fixture data for tests, transmitting binary data through text-only channels (chat, SMS, old email systems).
Frequently Asked Questions
What's the max file size?
Bounded by browser memory - most laptops handle 50-100 MB comfortably. Larger files cause the browser tab to slow. Note that the Base64 output is ~33% larger than the source file, so a 50 MB PDF becomes a 67 MB Base64 string.
Why is my Base64 output huge?
Base64 encoding always increases size by ~33% (3 bytes -> 4 chars). A 1 MB file becomes a ~1.34 MB Base64 string. If you need smaller payloads, consider gzipping the file first, then Base64-encoding the gzipped output.
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