How this converter works
Most image converters on the web are a web page in front of a server. You choose a file, the file is uploaded, a machine somewhere else re-encodes it, and a download link comes back. This one has no server step at all. When you drop a file into the box above, your browser reads it from your disk, decodes it into a picture, draws that picture onto an off-screen canvas at its original pixel dimensions, and asks the browser's own image engine to encode it again in the format you chose. The result is a new file created in your device's memory and offered to you as a download.
Two formats need a little more than the browser provides on its own. AVIF output uses an open-source encoder compiled to WebAssembly, and HEIC input uses an open-source decoder in the same form. Both are served from this site and both run inside your browser, exactly like the rest of the tool. They are fetched only the first time you actually need them, which keeps the page fast for everyone converting ordinary JPGs and PNGs. What is downloaded is the codec, a piece of software; what is never uploaded is your picture.
Why converting on your own device matters
The privacy claim here is a structural one rather than a promise. Because the conversion is performed by code running in your browser, there is no point in the process at which the image data is sent across the network. Photographs of your family, screenshots containing account details, scans of documents, and product shots taken inside your home all stay where they already were.
That has practical side effects beyond privacy. There is no upload wait, so conversion is limited only by how fast your own device works, and a batch of images processes in seconds rather than in however long your connection takes. There is no file size cap imposed by a server, because no server is involved. There is no queue at busy times, no account, and no watermark. And once you close the tab, nothing remains: no copy of your file exists anywhere for anyone to delete, retain, or leak.
It also means the converted file is genuinely clean. Since the new image is written from redrawn pixels rather than copied from the original, the EXIF metadata block does not travel with it, so camera details and any GPS coordinates are left behind. Our guide to image metadata explains what that block contains and why it is worth thinking about before you send a photo to a stranger.
When you would actually convert an image
An iPhone photo nobody else can open
You email a photo and the reply is "it won't open". iPhones save pictures as HEIC, which many Windows computers, older applications, and upload forms cannot read. Converting to JPG makes the file universal, and it takes about ten seconds. Use HEIC to JPG, or read why iPhones use HEIC if you would rather stop the problem at the source.
An upload form that keeps refusing your file
Job portals, insurance claims, and school systems tend to accept only JPG or PNG and often cap the file size. A phone photo of a document is frequently both the wrong format and too large. Converting to JPG at 85 percent quality usually fixes both problems at once and leaves the text perfectly legible.
An image saved from a website that will not open
Save a picture from a modern site and you may get a .webp or .avif file that your photo editor refuses. Both are ordinary images your browser can already read, so WebP to JPG and AVIF to JPG convert them into something every program understands.
Photos going onto a website you run
Here the priority flips: you want the smallest file that still looks right. Converting JPGs to WebP typically saves 25 to 35 percent at the same visual quality, which is a real improvement across an image-heavy page. AVIF usually saves more again, at the cost of slower encoding.
A screenshot that is far too big to send
Screenshots of photographs or video frames are often saved as PNG, which stores every pixel exactly and produces a large file. Converting to JPG can cut that dramatically. Screenshots of text are the opposite case: keep those as PNG, because JPG compression smears small letterforms.
A favicon for a site you are building
Drop a square PNG in, choose ICO, and you get a multi-size icon containing 16, 32, 48, and 256 pixel versions in one file. The favicon guide includes the line of HTML that installs it.
Quality, size, and the slider
PNG and ICO are lossless: they record exactly the pixels they were given, which is why the quality slider disappears when you select them. JPG, WebP, and AVIF are lossy, meaning the encoder is allowed to discard fine detail in exchange for a much smaller file, and the slider decides how much freedom it has.
The default of 90 percent is a deliberately safe starting point. In normal photographs the difference from the original is not visible at ordinary viewing sizes, while the file is a fraction of a lossless equivalent. Lowering the setting to around 80 saves more with very little visible cost; below roughly 60 the damage starts to show as haloing around sharp edges, blockiness in smooth skies, and smeared color in saturated areas. There is no universally correct number, only the lowest setting at which you cannot see a problem on the screen where the image will be used, which is why every converted file shows its before and after size so you can judge for yourself.
One thing worth knowing: files sometimes get bigger. Converting a photograph to PNG, or an iPhone HEIC to JPG, produces a larger file because the destination format stores the same picture less efficiently. That is arithmetic, not a fault. Our guide to size versus quality explains which lever actually shrinks a file and in what order to pull them.
What the converter supports
- Output formats: PNG, JPG, WebP, AVIF, and ICO.
- Input formats: any image your browser can display, which covers JPG, PNG, WebP, AVIF, GIF, BMP, and ICO, plus HEIC and HEIF from Apple devices.
- Batches: up to 50 images at once, with a Download all button when more than one has been converted.
- Dimensions: preserved exactly. The converter changes format and compression, not size in pixels.
- Transparency: preserved by PNG, WebP, AVIF, and ICO. JPG cannot store it, so transparent areas are filled with white rather than turning black.
- Animation: not preserved. An animated GIF converts to a still image of its first frame, since none of the output formats here hold animation.
- Favicons: ICO output builds a single file containing 16, 32, 48, and 256 pixel versions, with a non-square source scaled to fit and centered.
Quick answers
Are my images uploaded anywhere?
No. Every conversion happens inside your browser on your own device. The file you drop in is read locally, redrawn, and encoded locally, and the result is handed straight back to you for download. Nothing about the picture is transmitted.
Is there a limit on file size or how many images?
There is no fixed file size limit, because there is no server imposing one. The practical ceiling is your own device's memory. The one hard limit is 50 images per batch, which exists to stop an accidental drop of a whole photo library from locking up your browser.
Does converting reduce the quality?
Converting to PNG or ICO is lossless and changes nothing. Converting to JPG, WebP, or AVIF re-encodes the picture, so a small amount of detail is discarded, but at the default 90 percent quality that difference is invisible in normal viewing.
Why did my transparent image come out with a white background?
You converted it to JPG, which has no way to store transparency. Transparent areas are filled with white before encoding so they do not come out black. Choose PNG, WebP, AVIF, or ICO instead to keep the transparency.
There are more than twenty further answers on the frequently asked questions page, covering batches, animated images, metadata, troubleshooting, and choosing between formats.
Guides and one-click converters
Every page on the site is listed in all guides and converters. The most useful starting points:
- Image format guide: JPG vs PNG vs WebP vs AVIF vs HEIC vs ICO, side by side.
- JPG vs PNG: the everyday decision, explained properly.
- WebP explained: how much smaller it really is, and where it works.
- What is HEIC: why iPhones use it and how to share those photos.
- PNG transparency: alpha channels, and why logos get white boxes.
- Image size vs quality: what actually shrinks a file.
- Converting for email, web, print, and social: the right settings per destination.
- Image metadata and EXIF: what your photos carry, and what conversion removes.
One-click conversions with the format preselected: HEIC to JPG, HEIC to PNG, WebP to JPG, JPG to WebP, PNG to JPG, JPG to PNG, AVIF to JPG, and PNG to ICO favicon.