The quick answer: a decision table
Pick the wrong format and a logo comes out blurry, or a photo comes out several times too big. Find your picture in the table and use the format next to it.
| What you have | Use | Why |
|---|---|---|
| A photo to send or upload to a form | JPG | Every phone, camera, website and print service opens it, and files stay small. |
| A photo attached to an email | JPG | Mail apps and older software are where WebP and AVIF are most often refused. |
| A photo on your own website | WebP, or AVIF with a JPG fallback | Usually smaller than JPG at a similar look. Current browsers open WebP. |
| A screenshot with text | PNG | Exact pixels keep letters sharp. A JPG can add fuzz around them. |
| A logo, icon or cut-out with see-through areas | PNG (WebP or AVIF on a website) | JPG cannot be transparent. |
| A QR code or barcode image | PNG, or SVG for print | Hard edges have to stay hard. A lossy JPG blurs the squares and can stop a code scanning. See QR codes that keep working. |
| A picture for print | Your original, or a high quality JPG | Print services differ in what they accept. Ask which formats they open. |
| An animation | GIF, or a short video | The image converter keeps only the first frame of an animated GIF or WebP, and the image compressor leaves animated files as they are. To make a looping GIF from a video, use Video to GIF. |
If you remember one rule: JPG when the file must open anywhere, PNG when you need exact pixels or transparency, WebP when the file is for a website. To switch a file from one to another, the image converter does JPG, PNG, WebP and AVIF in bulk, and nothing is uploaded. Your pictures stay in the browser tab.
Image ConverterAdd your pictures, pick JPG, PNG, WebP or AVIF, and compare the size of each result before you download.Open itEach format in a few lines
JPG
JPG is lossy: it throws away detail you are unlikely to notice to keep photos small. It cannot be transparent, and every time you edit and re-save one, a little more quality goes. Around quality 90 is a safe default for photos. Below about 75 you may start to see blocks and smudges in smooth skies and around text.
PNG
PNG is lossless. It stores every pixel exactly and supports transparency, so it suits screenshots, logos, text, line art and working copies you will edit again. The price is size on photos. A 12 megapixel iPhone photo that was 2.7 MB as a HEIC became a 15.7 MB PNG in the HEIC converter's test.
WebP
WebP can be lossy or lossless, supports transparency, and is usually smaller than a JPG with a similar look. In the image compressor's tests it came out about 4 to 5 percent smaller than JPG for two large, detailed photos and 20 to 45 percent smaller for small, smooth pictures. The gain is largest where JPG wastes the most bytes.
AVIF
AVIF often makes the smallest files of all and supports transparency too, though soft edges can change slightly. It takes longer to create. A 3.1 megapixel photo took about 2.7 seconds in the converter's test. In the same test, a 967 KB high quality JPG became a 372 KB AVIF at the default quality, which is not a fair comparison. On a small picture scored for similarity, the AVIF was about 39 percent smaller than a JPG with the same score, and the real gap varies by picture. AVIF files made here carry no camera or GPS data.
Browser and app support
Support is the part that changes, so treat this as a snapshot and check before you depend on it.
| Format | Browsers | Other software and forms |
|---|---|---|
| JPG | All | All |
| PNG | All | All |
| WebP | Current Chrome, Edge, Firefox and Safari | Some older programs, print services, upload forms and email tools do not open it. |
| AVIF | Chrome 85, Firefox 93, Safari 16.4 and Edge 121 and later (per the caniuse figures in the AVIF converter's notes) | Many programs outside browsers still cannot open it. |
On a website, the safe pattern is the HTML picture element: a source of type image/avif or image/webp first, then your JPG in the img tag inside it. Browsers pick the first format they understand, and the rest fall back to the JPG. When a file has to open on someone else's computer, send JPG or PNG.
Convert between formats without a second round of damage
Going to JPG, lossy WebP or AVIF discards some detail, and doing it twice adds up. Going to PNG loses nothing further, but cannot bring back detail an earlier lossy format already removed. So convert once, from your best original, and keep that original.
- PNG to JPG: PNG to JPG starts at quality 90. JPG has no transparency, so see-through areas are filled with white or any color you choose. Photos usually shrink to a fraction of their PNG size, but a screenshot or logo with few colors can come out larger and fuzzier.
- JPG to WebP: JPG to WebP starts at quality 85. The JPG was already compressed once, so lossy WebP compresses it a second time, which is hard to see at 85 and above. The lossless option keeps every decoded pixel, but for photos the file is often bigger than the JPG itself.
- JPG to AVIF: JPG to AVIF starts at quality 65 and takes longer. Open one result at full size before you replace your JPG files, and keep the JPGs as the fallback.
- Any format, smaller: the image compressor can change the format while it compresses. For JPG, WebP and AVIF results it picks, picture by picture, the lowest quality that still looks like the original, and the list shows if a result came out bigger.
Colors are converted to sRGB in the converters, and in the compressor whenever it re-saves a picture, so a photo shot in a wide color range can look slightly less vivid. A picture the compressor returns unchanged keeps its color profile.
What goes wrong, and the fix
- The logo is blurry or has fuzzy edges. It was saved as a JPG. Go back to the original PNG or SVG. Converting the JPG to PNG stores the fuzz exactly, and does not remove it.
- A transparent logo has a white or black box. JPG cannot be transparent, and the converter fills the area with a color. Keep it as PNG, or WebP on a website.
- A photo file is enormous. It is probably a PNG. Convert it to JPG or WebP. PNG photos are typically several times larger.
- A form rejects the file as the wrong type. WebP and AVIF are the usual suspects. Turn them back into JPG with WebP to JPG or AVIF to JPG. An iPhone HEIC photo causes the same trouble, and open HEIC photos on Windows covers it. YouTube recommends JPG or PNG for thumbnails, and YouTube thumbnail size and safe zones covers the rest of its limits.
What to do next
If the picture is going on a site, compress images for your website covers sizes, quality and a batch workflow. If a form has a size limit, reduce a photo to 200 KB or less shows how to hit it. And if your source is a document, convert a PDF to JPG turns its pages into pictures.