Article
Choosing the right image format
JPEG, PNG, WebP, HEIC, AVIF: picking an image format sounds technical, but the decision comes down to three questions: what is in the image, where is it going, and does it need a transparent background? This article cuts through the noise and gives you a clear answer for the most common cases.
JPEG for photos, PNG for graphics with sharp edges
JPEG works by discarding visual detail that the eye barely notices, which is why it compresses photographs extremely well but turns text, logos and screenshots ugly at moderate quality levels. PNG uses lossless compression: every pixel is preserved exactly. That makes it the right choice for diagrams, screenshots with text, logos, and any image where you need a transparent background. If you are unsure, open the file and zoom in: if the edges of text or lines look jagged or blurry, switch to PNG. If the image is a photograph with continuous tones, JPEG is almost always the better choice for file size.
WebP is the modern default for the web
WebP, developed by Google and supported by every modern browser, delivers smaller files than both JPEG and PNG for the same visual quality. A WebP photo is typically 25 to 35 percent smaller than its JPEG equivalent. WebP also supports transparency, so it can replace PNG in most web contexts. The main practical limit is that some older software (certain email clients, older image editors, iOS before version 14) does not open WebP natively. For anything displayed in a browser, WebP is the safe choice. For files you will share with people outside a browser context, JPEG or PNG remains more interoperable.
HEIC, AVIF and when to convert
HEIC is the default format on iPhone cameras since iOS 11. It produces sharp photos at roughly half the size of comparable JPEG files, but it is not universally readable: Windows does not open it without a codec, most online forms do not accept it, and sharing a HEIC file with someone outside the Apple ecosystem often means they cannot open it at all. Converting to JPEG or WebP before sharing is almost always the right move. AVIF is the successor to WebP: it compresses even further and handles HDR content well, but support in non-browser software is still limited as of 2025. Use it on the web when you control the environment; convert to JPEG or WebP for broader reach.
A practical decision guide
Photo for a website: use WebP, fall back to JPEG if you need maximum compatibility. Screenshot or diagram with text: use PNG. Logo with transparency: use PNG or WebP. iPhone photo to share broadly: convert HEIC to JPEG. Image for an online form that only accepts JPEG or PNG: convert accordingly. If you need the smallest file for a web image and your tools support it, AVIF gives the best compression today. The image compressor here lets you convert to any of these formats and adjust quality, all without sending your file to a server.
Tools in this article
Frequently asked questions
Does converting to WebP reduce image quality?
Converting from a lossless source (PNG) to WebP at a high quality setting produces a file that is visually identical to the original at a fraction of the size. Converting from JPEG to WebP recompresses the image, which can introduce a small additional quality loss. To minimise this, convert from the original source rather than from an already-compressed JPEG, and set the quality level to 80 or above. The difference is rarely visible at normal viewing sizes.
Why do some platforms reject WebP or AVIF?
Older software and some online forms validate file extensions or MIME types against a fixed list that predates modern formats. If a platform rejects WebP, convert to JPEG or PNG before uploading. AVIF is newer and has even less legacy support. Both formats are widely accepted in browsers and modern image editing software, but when you do not control the destination, JPEG and PNG remain the safest choice.