ImageLosslessRuns in your browser

PNG to ICO Converter

Turn PNG files into ICO in a couple of clicks. PNG is a lossless image format with full alpha transparency; ICO is a multi-resolution icon container for favicons and apps. 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

PNG files (.png) · up to 120 MB each

or paste files from your clipboard

Ready when you are

Drop a PNG file above and FileTools360 will turn it into ICO — right here on your device, without uploading anything.

⌘K to search converters

How to use it

1
Add your PNG files
Drag them onto the drop area, choose them from your device, or paste them from your clipboard. You can queue several at once. Nothing is sent anywhere — the file stays on this device.
2
Adjust the settings if you want to
The defaults suit most people. Open Advanced to control metadata removal.
3
Convert and download
Press Convert. Everything happens on your own device — nothing is uploaded. Download files one by one, or grab them all as a ZIP.

Privacy, in plain words

Is it safe? Your PNG file 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 PNG file 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.

PNG and ICO explained

PNG is a lossless raster format built to replace GIF. It stores every pixel exactly as given and supports a full 8-bit alpha channel, which means genuine partial transparency rather than the single transparent colour GIF offers.

ICO is a container that holds several versions of the same icon at different sizes, so the operating system or browser can pick the one that fits. It is capped at 256×256 pixels.

Where PNG files come from: Screenshots, exported logos and UI assets, and anything designed rather than photographed.
Where ICO is used: Website favicons and Windows application icons.

PNG vs ICO

The two formats solve different problems, which is why converting between them involves trade-offs rather than a straight upgrade.

PNG compared with ICO
Property	Source	Target
Compression	Lossless	Lossy or lossless
Transparency	Yes	Yes
Animation	No	No
Introduced	1996	1985
Browser support	Universally supported.	Browsers and Windows. Sizes are capped at 256×256.

PNG is stronger at: Completely lossless — re-saving never degrades the image. Full alpha transparency, including soft edges and shadows. Sharp text and hard edges stay sharp.
ICO is stronger at: Holds multiple resolutions in one file. The format browsers expect for favicon.ico. Supports transparency.

Why convert PNG to ICO?

People make this switch when they run into the limits of PNG: you are publishing photographs on the web, where it will be several times larger than it needs to be. ICO is the better fit when you are making a favicon or a Windows application icon.

PNG limitations that prompt the switch: Much larger than JPEG or WebP for photographic content. No animation in practice (APNG exists but support is inconsistent). No native support for CMYK or print colour workflows.
What you give up: Capped at 256×256. Not a general-purpose image format.

Does converting PNG to ICO reduce quality?

Both formats store the content without discarding data, so this conversion preserves it exactly. The file size may change because the two formats compress differently, but the content itself is unaffected.

Measured, not estimated

What converting PNG to ICO actually costs

On every sample measured, the ICO came out smaller — 6× smaller at worst and 8× smaller at best.

Each row is one sample chosen to isolate a property these formats treat differently.
Sample	PNG in	ICO 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.	356 KB	44.1 KB	−88%
A hard clipThe other end — pink noise, or dense video grain. Close to incompressible by design, and the worst case for every codec.	1.1 MB	210 KB	−82%

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

Source

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.

Target

Windows Icon

Multi-resolution icon container for favicons and apps.

Extensions: .ico
MIME type: image/x-icon
Best for: Favicons · Windows application icons
Compatibility: Browsers and Windows. Sizes are capped at 256×256.

Icons are capped at 256×256 by the ICO format itself. Larger sources are downscaled.

Good to know

PNG to ICO Converter — questions

How do I convert PNG to ICO?

Drop your PNG file onto the area above, then press Convert. The ICO file saves straight to your device. You do not need an account, and there is no watermark.

Is it safe to convert PNG files here — are they uploaded to a server?

No, nothing is uploaded. On most online converters, pressing the button copies your file across the internet onto a computer owned by that website; it is converted there and sent back. That copy is what "upload" means, and it is the part that puts your file out of your control. This site does not do it. Your PNG file is read and converted by the browser you are using right now and never leaves this device, so there is no copy for anyone to store, read or hand over. You can prove it: turn off your Wi-Fi after this page loads and the conversion still works.

Can I convert confidential PNG files, like bank statements or contracts?

Yes, and that is the case this site 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 someone else's hardware, no retention period to read about and no staff with access. Nothing is logged about the file either: not its name, not its size, not its contents. The one thing worth saying plainly is that this protects the file in transit and at rest on our side, not from anything already on your own computer.

What should I know before converting PNG to ICO?

Icons are capped at 256×256 by the ICO format itself. Larger sources are downscaled.

Does converting to ICO reduce quality?

No. ICO is a lossless format, so the conversion preserves exactly what is in your PNG file. Note that it cannot recover detail that was already discarded when the PNG was first created — a lossless container does not undo earlier compression.

How large a file can I convert?

Up to 120 MB per file for this conversion. Because the work happens in your browser, the practical limit is your device's memory — larger files work on a desktop with plenty of RAM and may fail on an older phone.

Can I convert several files at once?

Yes. Add as many as you like and press Convert All. Each file is processed independently, so one failure does not stop the rest, and you can download everything together as a ZIP.

Can I use this on my phone?

Yes. FileTools360 works in mobile browsers on iOS and Android, including choosing files straight from your camera roll. Very large images may run out of memory on a phone — those are better converted on a laptop.