Key takeaways
- 01JPG is for photos, PNG is for graphics and transparency, WebP and AVIF are newer formats that beat both on size.
- 02AVIF usually produces the smallest files, WebP is the best-supported modern format, and JPG/PNG remain the safest for compatibility.
- 03Lossy formats (JPG, WebP, AVIF) discard detail to shrink files; PNG is lossless and keeps every pixel.
The one concept that explains everything: lossy vs. lossless
Before comparing formats, know the split that drives all of them. Lossless formats store every pixel exactly and can be reopened and re-saved forever with no degradation — PNG is the main one. Lossy formats throw away information the eye is unlikely to notice, trading a little quality for a much smaller file — JPG, WebP, and AVIF all do this. There is no single "best" format because the right choice depends on whether your image is a photograph, a logo, or a screenshot, and on how much you value size versus compatibility.
The quick decision rule
If you remember nothing else, remember these five lines.
- 01Photograph for the web, maximum compatibility: use JPG. It is understood by everything and compresses photos well.
- 02Logo, icon, screenshot, or anything needing transparency: use PNG. It keeps sharp edges and a transparent background perfectly.
- 03Modern website where you want smaller files and control the audience: use WebP. It beats JPG and PNG on size and is supported by all current browsers.
- 04Cutting-edge site chasing the smallest possible files: use AVIF. It usually wins on size, especially for photos, with a fallback for older browsers.
- 05Animation without video: WebP or AVIF (animated) beat the old GIF on size and colour.
The four formats, one by one
JPG (or JPEG) is the veteran. It was built for photographs and uses lossy compression tuned for the smooth gradients of real-world images. It has no transparency and its compression can leave blocky artifacts around sharp edges and text, which is why it is wrong for logos and screenshots. Its superpower is universal support: every device, editor, and website accepts a JPG.
PNG is the lossless choice. It preserves every pixel and supports full transparency, making it the standard for graphics with hard edges, text, UI screenshots, and anything with a see-through background. The cost is file size: a PNG photograph is often several times larger than the same photo as a JPG, so PNG is a poor pick for photographic content on the web.
WebP, from Google, is the modern all-rounder. It offers both lossy and lossless modes plus transparency and animation, and at similar quality it produces files roughly 25-35% smaller than JPG and often much smaller than PNG. Every current browser supports it, which makes it the pragmatic default for a fast website today.
AVIF is the newest of the four, based on modern video-codec technology. It typically achieves the smallest files of all — frequently beating WebP by a wide margin on photos — and supports transparency, wide colour, and high dynamic range. Support is now broad but not quite universal, so sites usually serve AVIF with a WebP or JPG fallback for the last few older clients.
How to convert between formats
Converting is a two-minute job and happens entirely in your browser, so the originals never leave your device.
- 01
Pick the right converter
Choose the tool that matches your direction — for example PNG to JPG to shrink a graphic-heavy photo, or WebP to JPG to restore compatibility.
- 02
Drop in your image
Add one file or a whole batch. The conversion runs locally in the browser.
- 03
Set quality if it is lossy
For JPG, WebP, or AVIF output, choose a quality level — higher keeps more detail, lower makes a smaller file.
- 04
Download the result
Save a single image or export the batch. Keep your originals in case you need them again.
Putting it together for a real page
A well-optimized web page rarely uses one format for everything. Photographs go out as WebP or AVIF for speed, with a JPG fallback. Logos, icons, and anything with transparency stay as PNG — or better, as SVG if they are vector art — because a lossy format would fuzz their crisp edges. Screenshots of text look best as PNG for the same reason.
If you are unsure whether a switch is worth it, convert one representative image and compare both the file size and how it looks at full zoom. The size drop from JPG to WebP or AVIF is often dramatic with no visible quality loss, which is exactly the win that makes pages load faster. When compatibility matters more than bytes — an email attachment, an old system, a print shop — fall back to JPG or PNG, the two formats that work everywhere.
Image format FAQ
Is WebP better than JPG?
For the web, usually yes. WebP produces files roughly 25-35% smaller than JPG at similar quality and also supports transparency and animation. JPG still wins when you need maximum compatibility, such as an attachment for an unknown recipient.
When should I use PNG instead of JPG?
Use PNG for graphics, logos, icons, screenshots, and any image that needs a transparent background or crisp edges. Use JPG for photographs, where PNG would be needlessly large.
Is AVIF better than WebP?
AVIF usually produces smaller files than WebP, especially for photographs, and supports wide colour. WebP has slightly broader support and faster encoding, so many sites use AVIF with a WebP fallback.
Does converting between formats lose quality?
Converting to a lossy format (JPG, WebP, AVIF) discards some detail, and repeated lossy saves compound the loss. Converting to PNG is lossless. Always convert from the highest-quality original you have.