Choose JPG, PNG or WebP for smaller, usable images

Choose dimensions before chasing compression

A 5000-pixel-wide photograph is usually unnecessary for a small product thumbnail. Resize to the dimensions actually needed, then adjust format and quality. Keep the original if the image may later be printed or cropped differently. A percentage reduction can look impressive while the resulting file is still larger than the destination requires.

Rough sizes for common destinations

Matching pixel dimensions to the destination matters more than any quality setting. These are practical starting points rather than rules, so check the requirements of the site or platform you are using.

• A website article image: about 1200 to 1600 pixels wide, and under roughly 200 KB where possible.
• A small thumbnail or avatar: 200 to 400 pixels square.
• An email attachment or document photo: 1600 pixels on the long side is plenty for reading on a screen.
• A profile photo for a form: whatever the form specifies, often a fixed pixel size and a limit such as 100 KB.
• A print at 300 dpi: pixels equal to the print size in inches times 300, so a 6 by 4 inch print needs about 1800 by 1200 pixels.

Use JPG for continuous-tone photographs

JPG is widely compatible and often a good choice for photos without transparency. Lossy compression can soften details or create artifacts around sharp edges. Export from the original and inspect faces, text and high-contrast boundaries. Repeatedly saving an already-degraded JPG can add further loss. A higher quality setting cannot recover detail that was lost earlier.

A workflow when the limit is a number of kilobytes

Forms that say “under 200 KB” are common. The Image Compressor has a target size box for exactly this. It looks for the highest quality that still fits, and scales the dimensions down if quality alone cannot get there. It lists the size it reached. If a file is already smaller than your target, it keeps your original rather than recompressing it.

If the result looks too soft, resize first to the dimensions the form really needs, then compress. Starting from a 4000-pixel photo and forcing it under 100 KB at full size produces heavy compression artifacts, while a 1000-pixel version of the same photo can fit comfortably with good quality.

Use PNG when sharp edges or transparency matter

PNG supports transparency and is useful for screenshots, diagrams and interface graphics. It may be much larger than a lossy format for a detailed photograph. Changing a quality slider does not necessarily reduce PNG size because browser PNG encoding is lossless. Reduce dimensions or choose another format when a smaller file matters more than exact pixel preservation.

WebP, and when not to use it

WebP is typically 25 to 35 percent smaller than JPG at similar quality, and all current major browsers display it, which makes it a good default for websites you control. The risks are outside the browser: some email programs, older desktop software, print services and upload forms still insist on JPG or PNG. If you do not know where the image will end up, JPG is the safest choice for photos and PNG for graphics.

You can keep both. Use the Image Converter to make a WebP for your website and keep a JPG for sharing. Convert from the original each time, not from an already compressed copy.

Consider WebP when the destination supports it

WebP can provide small files and transparency, but confirm that the receiving site, app or workflow accepts it. The best result depends on the image and encoder. Compare actual output sizes and inspect the image rather than assuming one format always wins. When converting a transparent image to JPG, choose a suitable background because JPG cannot retain the alpha channel.

Transparency, backgrounds and screenshots

PNG and WebP can store transparent areas; JPG cannot. Converting a transparent logo to JPG fills the transparent area with a solid color, which is usually white or black unless you choose otherwise. Choose a background color that matches where the image will be placed, or keep the logo as PNG.

Screenshots deserve PNG because they contain sharp text and flat color, which JPG blurs at the edges of letters. If a screenshot PNG is too large, reduce the pixel dimensions first. A full-screen capture at high resolution is rarely needed to show a setting or an error message.

Review a batch before publishing

Test one photo, one screenshot and one transparent asset before applying settings to a large group. Check orientation, color, dimensions, filenames and transparency. Metadata may not be preserved by canvas-based exports, so keep originals if camera details or embedded profiles matter. For sensitive images, local processing reduces upload exposure but does not remove risks from browser extensions, shared devices or the final sharing destination.

HEIC photos from phones

Many phones save photos as HEIC, which Windows apps, many websites and some printers cannot open. Convert to JPG with the HEIC to JPG tool before sharing. Expect the JPG to be larger than the HEIC, and note that extras such as Live Photo motion are not kept. If you would rather avoid the problem, iPhone users can choose Settings, Camera, Formats, Most Compatible so new photos are saved as JPG.

Common mistakes

• Compressing the same image repeatedly, which stacks losses. Always go back to the original.
• Enlarging a small image to make it “bigger”. Enlarging adds pixels but no detail.
• Using PNG for photographs and wondering why the file is huge.
• Forgetting that metadata, including GPS location, can travel with the original file; check with the Image Metadata tool before posting photos publicly.
• Judging quality from a thumbnail. Check faces, text and edges at 100 percent.

Questions people ask

Why did my PNG barely shrink when I lowered the quality? PNG is lossless in browser exports, so a quality slider does not change it much. Reduce dimensions or switch format.

Will converting JPG to PNG improve quality? No. It preserves what the JPG already has, and the file usually gets bigger.

What quality setting should I use for photos? Around 75 to 85 percent is a common range. Check the result at full size for your own image.

Do I lose the date and location when I compress? Canvas-based exports usually drop metadata, but do not rely on it. Use the Image Metadata tool when privacy matters.

A quick decision guide

When you do not want to think about it, use these defaults. Photograph for the web: WebP or JPG at 75 to 85 percent quality, resized to the display width. Photograph that must open anywhere: JPG. Logo or icon with transparency: PNG, or SVG if you have the vector file. Screenshot with text: PNG, reduced in dimensions if large. Image for a document upload with a size limit: JPG, resized and compressed to the stated number of kilobytes. Image that will be edited later: keep the original and export copies, rather than editing a compressed one.

Each of these is a starting point. Check the result at full size, because the right setting depends on the content: a photo of a clear sky shows compression banding sooner than a busy street scene, and a screenshot with small text shows blur sooner than a photo of a landscape.