JPG vs PNG vs WebP: Which image format should you use?

Start with the destination. If an application form accepts JPG only, its format requirement decides the answer. When you have a choice, pick a format based on the image and how the recipient will use it.

Choose by the type of image

Format	Good starting point	What to check
JPG	Photos with many colours and gradual shading	The format uses lossy compression and cannot keep a transparent background.
PNG	Screenshots, diagrams, and logos with transparency	Preserves exact pixels, but a large photo saved as PNG may use more space.
WebP	Photos and graphics for a website	Supports transparency and lossy or lossless encoding. Confirm the recipient or upload form accepts WebP.

MDN’s image format guide describes the formats and browser support. Your result will depend on the source image and the encoder.

Compare the outputs yourself

Take a photo for a web listing and a screenshot with small text. Use Image Converter to make copies in the formats the destination accepts. Keep the pixel dimensions the same for the first comparison, then look at the file sizes and open each result at actual size.

Check text edges in the screenshot and smooth gradients in the photo. A smaller file can look fine in a thumbnail and reveal visible compression at full size. For a transparent logo, view the result on both light and dark backgrounds to catch an unexpected solid fill.

When resizing matters more

If the website displays a photo at around 900 pixels wide, a much larger source image may add bytes without helping that use. Use Image Resizer to make a copy at the dimensions your layout needs. Then try Image Compressor if you still need a smaller download. Keep the original so you can produce a different size later.

Match the export to how people will receive it

For an email attachment or a portal upload, check the formats the recipient explicitly accepts before optimizing anything. A newer format can be a good fit for your own website and still be inconvenient for a colleague opening a file in an older editor. For a product image that needs a transparent background, use a format that retains transparency and check the export over a contrasting colour.

For a website, compare the same image where it will be displayed. A dark gradient in a banner is a good place to look for bands of colour, while a screenshot with fine text can expose fuzzy edges. If you need multiple sizes, export each from the master image so an existing compressed copy does not become the source for all the rest.

Try a small export test

Take a single input and make three copies with descriptive filenames. Write down the width, height, format, and byte size of each. Then judge the parts that matter to the project, such as the edge of a logo, a fine line in a chart, or facial detail in a listing photo. Start with the smallest result that passes those checks and that the recipient can open.

For a long-lived workflow, save the settings you used. The same export choice may work again for similar images, even though it can produce a different file size. See the image compressor comparison for ways to choose between a size target, visual comparison, and desktop optimization.