Image to Base64 Converter

Convert an image to a base64 string, data URI, or ready-to-use img tag.

FreeBrowser-basedInstant

Your files are processed locally in your browser and are not uploaded to our servers. Your image is read and base64-encoded entirely in your browser using JavaScript's FileReader/ArrayBuffer APIs — it is never uploaded or sent to any server.

How to use Image to Base64 Converter

Upload a JPG, PNG, WEBP, GIF, or BMP image and this tool reads the raw file bytes right in your browser and encodes them as base64. You get three ready-to-use outputs: the raw base64 string, a full data: URI you can paste directly into an img src or CSS background-image, and a complete HTML img tag snippet. Copy whichever one you need with a single click. Nothing is ever uploaded to a server — the image never leaves your device.

Key features

  • Raw base64 string output
  • Full data: URI ready to paste into src or CSS
  • Ready-made HTML img tag snippet
  • Live image preview before and after encoding
  • One-click copy button for each output format
  • Runs entirely offline in your browser — no uploads

Practical use cases

  • Embedding a small icon directly in CSS via a data URI to avoid an extra HTTP request
  • Embedding an image inline in an HTML email where external images might be blocked
  • Quickly testing an image in a data URI without hosting it anywhere
  • Embedding a small logo directly into a single-file HTML prototype

Supported formats

Accepted: jpg, png, webp, gif, bmp

Limitations

  • Base64-encoded images are always larger than the original file (roughly 33% overhead), which makes this impractical for large images meant for a live website — prefer a real hosted file for those
  • Very large source images will produce a very long string that may be unwieldy to work with by hand

Frequently asked questions

What is base64 encoding used for?
Base64 turns binary data, like an image's raw bytes, into a plain text string using only letters, numbers, and a few symbols. That makes it possible to embed an image directly inside HTML, CSS, or JSON without hosting it as a separate file.
Why is the base64 string longer than my original file?
Base64 encodes every 3 bytes of binary data as 4 text characters, so the encoded string is roughly 33% larger than the original file size. A 100 KB image becomes about 133 KB of base64 text — that overhead is normal and unavoidable.
Can I use the data URI directly in CSS?
Yes. Paste the data URI output into a background-image property, e.g. background-image: url("data:image/png;base64,...") — no separate image file or HTTP request needed.
Does this upload my image anywhere?
No. The file is read and encoded locally in your browser using JavaScript. It is never transmitted to a server, so your image stays private on your device.

Part of Image Tools