Use JPG for photos, PNG for graphics that need sharp edges or transparency, and WebP when you want the smallest file and your audience uses a modern browser. That is the short answer. The long answer depends on what is in your image and where it will be used, so let us look at each format in plain terms.
Choosing the wrong format is one of the most common reasons web pages load slowly and emails bounce for being too large. A few minutes of understanding saves a lot of megabytes later.
Key takeaways
- JPG is best for photographs and gives small files, but it loses a little quality each time you save.
- PNG keeps every pixel exactly and supports transparency, which suits logos, screenshots and text.
- WebP usually makes smaller files than both and supports transparency, and all current major browsers can show it.
- You can switch between formats for free in your browser, without uploading your files anywhere.
How image compression works (the 30-second version)
Every image format has to store a grid of coloured pixels. The difference is how it shrinks that grid. There are two big families.
Lossy formats throw away detail that your eyes are unlikely to notice. The file gets much smaller, but the discarded detail is gone for good. JPG is lossy. WebP can be lossy or lossless.
Lossless formats shrink the file without discarding anything. When you open the image, every pixel is exactly as it was. PNG is always lossless.
Because of this, a photo saved as PNG can be several times larger than the same photo saved as JPG, while a simple logo saved as JPG can look blurry around the edges.
The three formats explained
JPG: the everyday format for photos
JPG (also written JPEG) has been the standard for photographs for decades. Phones, cameras and most websites use it. It handles smooth colour changes, such as skies and skin tones, very well.
Good for:
- Photos of people, places and products
- Email attachments where size matters
- Anywhere you need maximum compatibility
Not so good for:
- Images with text, thin lines or flat colours, which can show fuzzy artefacts
- Transparency, because JPG does not support it
- Repeated editing, because every re-save as JPG loses a little more quality
A practical tip: keep your original file, and make a JPG copy for sharing. Do not keep editing and re-saving the same JPG.
PNG: sharp, exact and transparent
PNG stores every pixel without loss and supports transparent backgrounds. That makes it the natural choice for logos, icons, diagrams and screenshots, where crisp edges and readable text matter.
The price is file size. A large PNG photo can be very heavy. If you put big PNG photos on a web page, visitors on mobile data will wait longer than they need to.
Use PNG when you need a logo on top of a coloured background, when you are saving a screenshot with text, or when you plan to edit the image again later and want no quality loss.
WebP: the modern all-rounder
WebP is a format created by Google for the web. It can work in lossy mode (like JPG) or lossless mode (like PNG), and it supports transparency too. In typical use, a WebP file is noticeably smaller than a JPG or PNG that looks about the same.
All current major browsers can display WebP, so it is safe for most websites today. The main downsides are older software. Some older image editors, office programs and print services may not open WebP files. If you download a WebP and cannot use it, you can turn it into JPG or PNG with the free image converter.
One more point: WebP is a good choice when you care about page speed. Smaller images mean faster pages, and faster pages are better for visitors on slow connections or mobile data. For a small personal site, switching your biggest images to WebP is often the easiest speed improvement you can make.
Side-by-side comparison
| Feature | JPG | PNG | WebP |
|---|---|---|---|
| Compression | Lossy | Lossless | Lossy or lossless |
| Transparency | No | Yes | Yes |
| Best for | Photos | Logos, screenshots, text | Web images of any kind |
| File size | Small for photos | Large for photos | Usually smallest |
| Compatibility | Everywhere | Everywhere | All modern browsers; some older software |
Which one should you choose?
- Sending a photo by email or messenger: JPG.
- Putting a logo on a website or slide: PNG, or WebP if your site supports it.
- Saving a screenshot with text: PNG.
- Photos on your own website: WebP, with JPG as a fallback if you need it.
- Printing at a shop: JPG or PNG, because they are the safest.
If a file is simply too big, converting is only part of the answer. You can also reduce its dimensions with the image resizer or lower its quality slightly with the image compressor. Our guide on how to reduce image file size explains this step by step.
All three tools run in your browser. Your pictures are processed on your own device and are not uploaded to a server, which is helpful for private photos and for staying on the safe side of data protection rules.
Common mistakes to avoid
- Converting a JPG to PNG to «improve» quality. The detail that JPG lost does not come back; you only get a bigger file.
- Using PNG for every photo on a web page.
- Saving a logo as JPG and then wondering about the white box around it.
- Deleting the original after converting to a lossy format.
A final thought: you do not have to be perfect. If you remember one rule, remember this one: photos go in JPG or WebP, and anything with sharp lines or transparency goes in PNG or WebP. Test with your own images, compare the file sizes, and keep whichever version looks good and loads quickly.
Frequently asked questions
Is WebP better than JPG?
For most web use, yes: it is usually smaller at similar quality. But JPG is still more widely supported in older programs, so JPG remains useful for sharing and printing.
Does converting PNG to JPG lose quality?
Yes, a little, because JPG is lossy. For photos you will rarely notice. For screenshots with text you may see small blurry marks around letters.
Can I convert JPG to PNG to get transparency?
The conversion works, but the background will not become transparent by itself. You need an editor to remove the background first.
Are my files uploaded when I use the converter?
No. The conversion happens inside your browser, so your files stay on your device.
