Files & formats guide
What is Base64?
By Waleed Sheeraz, independent operator of A2Z Edit · Updated 2026-09-09
Base64 is a way to write binary data using a safe subset of ASCII text characters.
On A2Z Edit, Image to Base64 and Base64 to Image help you move between files and strings in the browser.
Steps
- Start with an image file when you need a string for code.
- Encode with Image to Base64.
- Paste the text into HTML, CSS, or JSON as required.
- Decode with Base64 to Image when you need a file again.
- Avoid Base64 for large media meant for CDNs.
Why it matters
Understanding Base64 prevents shipping huge inlined photos by accident.
Tips
- Expect about a 33% size increase versus raw bytes.
- Great for tiny icons; poor for multi‑megabyte photos.
- Keep originals—Base64 round-trips should not replace backups.
Not compression
Base64 makes files about a third larger as text. Use it for tiny inline icons, not heroes. A2Z Edit’s converters stay in the browser.
A data URI in CSS only helps when the image is smaller than an extra HTTP request. Decode on Base64 to Image when a template buried a PNG as text.
Frequently asked questions
Is Base64 encryption?
No. Anyone can decode it. It is encoding, not secrecy.
Why do APIs use it?
Text-friendly transports and JSON fields cannot always carry raw binary.
Base64 in email?
Attachments often use related encodings under the hood.
Related tools
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