JPG vs PNG vs WebP: which image format should you use?
Three formats cover almost every everyday need, and each one is the right answer somewhere. Choosing badly costs you either file size or quality; choosing well is a two-question decision. This guide explains how each format stores pixels, where it wins, where it fails and what to pick for the common cases.
JPG (JPEG): photographs and anything with gradients
JPG stores an image by discarding detail your eye is least likely to notice, which is why it can shrink a photo dramatically. It supports millions of colours but not transparency, and every re-save at a lossy quality removes a little more detail. Practically every device, browser, printer and form on earth accepts it.
Best for photos, scans of photos and any picture with smooth colour transitions. Weak for text, line art, sharp-edged logos and screenshots, where the discarded detail shows up as smudges around edges.
PNG: graphics, screenshots, transparency
PNG is lossless: what you save is exactly what you get back, however many times you open and re-save it. It supports full transparency, which makes it the standard for logos, icons and anything placed over a coloured background. The cost is size — a photo saved as PNG is typically several times larger than as JPG.
Best for screenshots with text, diagrams, logos, images that need transparency and any master copy you will edit again. Weak for photographs when file size matters.
A useful middle ground is an 8-bit or “lossy” PNG: the image is reduced to a palette of up to 256 colours. For interface screenshots and flat graphics the result is often indistinguishable and a fraction of the size. Toolkitta offers this as the Smaller PNG option.
WebP: smaller files for the web, with transparency
WebP was designed for websites. In lossy mode it usually produces files 25–35% smaller than JPG at comparable quality; in lossless mode it beats PNG. It supports transparency and is accepted by every current browser. Where it still trips people up is outside the browser: some older desktop software, email clients and upload forms reject it, and a few print services will not take it.
Best for images you publish on a website or app you control. Check compatibility before using it for a form upload or for a file someone else will open in unknown software.
HEIC and AVIF: the formats you receive but rarely send
Two newer formats arrive on your device without you choosing them. HEIC is what iPhones and recent Android phones save photos as: roughly half the size of an equivalent JPG at the same quality, with support for depth maps and Live Photos. AVIF is the web's newest format, smaller again than WebP, and it is what some websites now serve. Both decode in current browsers and phones, but many upload forms, older Windows PCs, email clients and print shops still refuse them.
The practical rule: keep your originals in whatever your camera made, and convert a copy to JPG (photos) or PNG (anything with transparency) when you need to share it somewhere that might not understand the newer format. Toolkitta's tools open HEIC and AVIF directly and save the result as JPG or PNG, so a phone photo can go straight into the compressor or cropper without a separate conversion step.
Side-by-side
- Compression: JPG lossy · PNG lossless (optionally 256-colour) · WebP lossy or lossless.
- Transparency: JPG no · PNG yes · WebP yes.
- Typical photo size at good quality: JPG 1× · PNG 4–10× · WebP 0.7×.
- Sharp text and edges: JPG poor at low quality · PNG perfect · WebP good.
- Compatibility: JPG universal · PNG universal · WebP all browsers, patchy elsewhere.
- Animation: none of the three in the way this tool uses them; animated images are rejected.
Decision list
- Photo for a form, email or unknown recipient → JPG, quality 75–85.
- Photo for your own website → WebP, with a JPG fallback if you support old browsers.
- Screenshot with text → PNG; use Smaller PNG if size matters.
- Logo or icon over a coloured background → PNG (or WebP on the web).
- Something you will keep editing → PNG, and export a JPG or WebP copy for sharing.
- Transparent image that must become JPG → choose the background colour deliberately; it replaces the transparency.
Converting between them
Converting from a lossy format to a lossless one does not recover detail that was already discarded; a PNG made from a JPG is just a larger copy of the same picture. Converting the other way is where the savings are. In the compressor, choose a format under Advanced settings; the original format is kept unless you change it, so nothing is converted by accident.