ImageLosslessRuns in your browser

Image to Base64

Turn an image into a data URL you can paste straight into CSS or HTML. The conversion is lossless — every pixel, sample or byte in the source is preserved.

Not uploaded to any serverConverted on this deviceGone when you close the tabHow this works

Drop your files here

JPG, PNG, WebP, AVIF and 4 more formats · up to 20.0 MB each

or paste files from your clipboard

Ready when you are

Turn an image into a data URL you can paste straight into CSS or HTML. Everything happens in this tab; nothing is sent anywhere.

⌘K to search converters

How to use it

1
Add your files
Image to Base64 works with JPG, PNG, WebP, AVIF, GIF, SVG, ICO and BMP. Drop them in, browse for them, or paste from your clipboard.
2
Choose your options
Tune the output settings — or leave the defaults, which are sensible.
3
Run it and download
Press the button and save the result. Everything happens on your device, and nothing is uploaded.

Privacy, in plain words

Is it safe? Your image is not uploaded anywhere

What “uploaded” normally means. On most online converters, pressing the button copies your file across the internet onto a computer owned by that website. That copy is what the word “upload” means, and it is the part nobody explains.

What happens instead. This site does not do it. There is no server here that receives files, so your image is read, converted and handed back by the browser you are using right now. It never travels — so there is no copy to store, read, leak or hand over.

Check it yourself in ten seconds

Turn off your Wi-Fi after this page has loaded, then convert a file anyway. It still works, because everything needed is already on your device.

The longer explanation of how this works, and the full detail of what is and is not stored on the privacy page.

Why this matters more than it sounds

Photographs carry more than what is in the frame — most also carry the time, the device and often the GPS coordinates where they were taken. It matters more than it sounds, because of what images usually are:

Photos of ID cards and licences

the usual way people send identity documents

Screenshots of bank transfers

account details, and proof of what you paid whom

Medical scans and photographs

X-rays, results, images of a condition

Photographs of children

family pictures that should stay in the family

A file that is never sent cannot be kept, leaked, subpoenaed or used to train anything. That is a property of how this works, not a promise about how carefully it is run.

How Image to Base64 works

Turn an image into a data URL you can paste straight into CSS or HTML. Everything happens inside this page: the file is read from your device into memory, processed there, and handed back as a download. It is never sent anywhere, and closing the tab discards it.

What it accepts: JPG, PNG, WebP, AVIF, GIF, SVG, ICO, BMP. Files are identified by their contents rather than their name, so a mislabelled file is still handled correctly.
What you get back: A TXT file, downloaded straight to your device.
What happens to the data: Nothing is re-encoded. The content that comes out is identical to the content that went in, byte for byte, and running it twice changes nothing.
Size limit: Up to 20 MB per file. Because the work happens on your own machine, available memory is the real constraint — a laptop handles far more than a phone.

The settings, and what each one changes

Image to Base64 has one setting, and the default is chosen to suit the common case.

Wrap as: Choose between Data URL, Raw Base64, CSS background rule, HTML <img> tag.

Worth knowing before you start

Base64 makes files about 33% larger. It is useful for tiny icons, not for photographs.

Measured, not estimated

What this tool actually does to a file

Encoding a photograph as a base64 data URL you can paste into HTML or CSS.

The result came out 1.3× larger than the file that went in.

Each row is one document, chosen because this tool behaves differently depending on what is inside the file.
Sample	In	Out	Change
An easy clipThe compressible end of the range — a clean tone, or a moving test pattern — where a codec does its best work.	12.5 KB	16.7 KB	+34%
A hard clipThe other end — pink noise, or dense video grain. Close to incompressible by design, and the worst case for every codec.	209 KB	278 KB	+33%

Produced by this site's own converter. The same code that runs in your browser, at the same default settings, so these are the bytes you would download.

Samples are generated from a fixed seed rather than taken from real photographs or documents, so the corpus is reproducible and carries no licensing question — and so the numbers predict the shape of your result rather than its exact size. Measured 2026-10-01. The method, and the command that regenerates every figure on this page, are on the how it works page.

About these formats

Accepts

JPEG Image

The universal lossy photo format.

Extensions: .jpg, .jpeg, .jpe, .jfif
MIME type: image/jpeg
Best for: Photographs · Email and messaging · Maximum compatibility
Compatibility: Opens everywhere — every browser, OS and device.

Accepts

Portable Network Graphics

Lossless image format with full alpha transparency.

Extensions: .png
MIME type: image/png
Best for: Transparency · Graphics and logos · Screenshots
Compatibility: Universally supported.

Base64 makes files about 33% larger. It is useful for tiny icons, not for photographs.

Good to know

Image to Base64 — questions

How does Image to Base64 work?

Turn an image into a data URL you can paste straight into CSS or HTML. Add your files above, adjust anything you want to change, and press the button. The result downloads straight to your device.

Is there anything I should watch out for?

Base64 makes files about 33% larger. It is useful for tiny icons, not for photographs.

Is Image to Base64 safe — are my files uploaded to a server?

No, nothing is uploaded. On most online tools, pressing the button copies your file across the internet onto a computer owned by that website, where it is processed and then sent back. That copy is what "upload" means. This tool does not do it: your file is read and processed by the browser you are using right now, stays on this device the whole time, and is discarded when you close the tab. Turn off your Wi-Fi after the page loads and it still works, which is the quickest way to confirm it.

Can I use this on confidential or personal documents?

Yes — that is the case it was built for. Because the file never leaves your device, a confidential document is no more exposed than it is sitting in your own folder: there is no transfer, no copy on anybody else's hardware, no retention period and no staff with access. Nothing about the file is logged either — not its name, not its size, not its contents.