Img Hut Choosing the wrong format is one of the most common reasons an image looks bad or weighs far too much. A photo saved as PNG can be many times heavier than it needs to be, while a logo saved as JPG gets fuzzy edges and loses its transparent background. For almost every image, the choice comes down to three questions: is it a photo or a graphic, does it need transparency, and where will it be used?
The short answer
| JPG / JPEG | PNG | WebP | |
|---|---|---|---|
| Compression | Lossy | Lossless | Lossy or lossless |
| Transparency | No | Yes, full alpha | Yes, full alpha |
| Animation | No | Only as APNG, rarely used | Yes |
| Best for | Photographs | Screenshots, logos, text, editing masters | Almost any image on a website |
| Watch out for | Blurred text, halos, no transparency | Very large photo files | Older software and some upload forms |
| Support | Universal | Universal | All current major browsers; not every app or form |
How JPG works, and why it suits photos
JPEG, standardized in 1992, was designed for photographs; .jpg and .jpeg are simply two extensions for the same format. The encoder separates brightness from color and usually stores color at a lower resolution, because our eyes are much less sensitive to fine color detail than to fine brightness detail. It then cuts the picture into 8 × 8 pixel blocks, describes each block as a mix of wave patterns and rounds away the patterns that contribute least. The quality setting decides how aggressive that rounding is.
On natural images full of gradual transitions and texture, this is extremely effective: a good JPG is a fraction of the size of the raw pixels with no visible difference. It fails on exactly the things photos rarely contain: sharp edges and flat colors. Text, thin lines and interface screenshots develop halos and “mosquito noise”, small colored lettering can bleed, and smooth gradients can break into bands at low quality. JPEG also has no alpha channel, so it cannot store transparency.
One more property matters in everyday work: every time you open a JPG and save it again, it is compressed again and loses a little more. Keep an original and always export from it, rather than editing the same JPG repeatedly.
How PNG works, and why it suits graphics
PNG, published in 1996, is lossless. Each row of pixels is passed through a simple prediction filter that makes it more repetitive, and the result is compressed with DEFLATE, the same family of compression used in ZIP files. Nothing is discarded; opening a PNG gives you exactly the pixels that were saved. That makes it the natural choice for screenshots, diagrams, charts, logos, pixel art and anything containing text, and for master copies you intend to keep editing. PNG also supports full alpha transparency, including soft, semi-transparent edges and shadows.
The cost appears with photographs. Lossless compression depends on repetition, and the fine noise in a photo has very little of it, so a photo stored as PNG is often several times larger than a high-quality JPG of the same picture. Dedicated optimizers can shrink PNGs by reducing them to a palette of 256 colors or fewer, sometimes called lossy PNG, but that is a separate step; a plain PNG export, including a browser’s, stores every color exactly.
How WebP works, and where it wins
WebP was introduced by Google in 2010 and offers two modes in one format. Lossy WebP is based on the way the VP8 video codec compresses individual frames: it predicts each block from its neighbours and stores only the difference. Lossless WebP uses a separate set of techniques designed for graphics. Both modes support transparency, and WebP can also hold animations.
Google’s own published comparison found lossy WebP files 25–34% smaller than JPEGs of equivalent measured quality, and lossless WebP files about 26% smaller than PNGs. Results vary from image to image, and on some pictures the gain is small, but in practice WebP is rarely worse than the best of JPG and PNG for a given picture.
Every current major browser displays WebP; Safari has supported it since version 14 on iOS 14 and macOS Big Sur in 2020. On the web, WebP is therefore a safe choice. Outside the browser, support is less complete: some older image editors, office suites, email clients and upload forms still refuse .webp files. When you send a file to someone else rather than publishing it yourself, JPG and PNG remain the safer options.
What about AVIF, GIF and SVG?
- AVIF is a newer format that often produces even smaller files than WebP, and current versions of the major browsers display it. Encoding is slower and browsers do not generally offer AVIF output through the canvas, so you need a dedicated encoder or a build tool to create it.
- GIF is limited to 256 colors per frame. For still images, PNG is better in every respect; for animations, a short video or an animated WebP is usually much smaller.
- SVG is not a pixel format at all but a description of shapes, so it stays sharp at any size. If you have your logo or icons as SVG, use SVG on your website. Convert to PNG only where SVG is not accepted, for example in link preview images for social networks or in favicons for older systems.
A five-question checklist
- Is it a photograph or photo-like, with gradients and texture? Use JPG, or WebP for your own website.
- Does it contain text, sharp lines, flat colors or interface elements? Use PNG, or lossless or high-quality WebP on your website.
- Does it need a transparent background? Use PNG or WebP, never JPG.
- Will it be edited again? Keep a lossless master, such as PNG or the original file, and export JPG or WebP copies from it.
- Where is it going? On a website you control, WebP is an excellent default. For email, documents, upload forms and printing services, JPG for photos and PNG for graphics are accepted almost everywhere.
Examples
- Product photo for an online shop: JPG at quality 80–85 or WebP at 75–80, resized to the largest size the shop displays.
- Screenshot for a help article: PNG. If the file is large, try WebP at a high quality; avoid JPG, which makes small text fuzzy.
- Logo in a website header: SVG if you have it; otherwise a PNG or WebP with a transparent background.
- Photos in an email newsletter: JPG, because support for WebP differs between email clients.
- A cut-out product image on a colored background: PNG or WebP to keep the transparency; a JPG would add a solid rectangle behind it.
Converting between formats
You can switch formats in the browser with PNG to JPG, which lets you choose the background color for transparent areas, JPG to PNG, and Compress Image, which saves JPEG, WebP or PNG at the quality you pick. Keep in mind that conversion never restores lost quality. Turning a JPG into a PNG preserves its compression artifacts exactly, and turning a PNG into a JPG applies lossy compression once, so convert from the best original you have and do it as the last step.
Tools mentioned in this guide
Compress Image
Reduce JPG, PNG or WebP file size by re-encoding at the quality you choose, with a before-and-after comparison.
PNG to JPG
Convert PNG to JPG with adjustable quality and your choice of background color for transparent areas.
JPG to PNG
Save a JPG as a lossless PNG so that further edits do not add new compression damage.
More guides
- How to Compress Images for Your Website Without Visible Quality Loss – A practical workflow: size images to how they are displayed, pick a format, find the lowest quality that still looks right, and serve the result with the right HTML attributes.
- Social Media Image Sizes in 2026: Dimensions, Aspect Ratios and Cropping – Common image sizes for Instagram, Facebook, X, LinkedIn, YouTube and Pinterest as of 2026, safe zones that get covered or cropped, and how to prepare an image in three steps.