Four formats, four very different jobs. Here's what each one is actually for, and when converting between them makes sense.
| Format | Best for | Weak point |
|---|---|---|
| JPG / JPEG | Photos, scanned documents — small file size | No transparency; loses a little quality every time it's re-saved |
| PNG | Logos, screenshots, graphics with sharp edges or text, transparency | Much larger file size for photos |
| WebP | Websites — smaller than JPG/PNG at similar quality, supports transparency | Still not universally supported by older software outside browsers |
| HEIC | iPhone photos — very efficient storage on-device | Barely supported outside Apple devices; most websites and Android apps reject it |
JPG uses "lossy" compression — it throws away image detail the human eye is less likely to notice, which is why a photo can shrink to a tenth of its raw size and still look fine. The trade-off is that detail, once discarded, is gone; re-saving a JPG repeatedly (edit, save, edit, save) compounds the quality loss slightly each time. JPG has no support for transparency, so a logo saved as JPG will always get a solid background instead of a see-through one.
PNG uses "lossless" compression — nothing is discarded, which is exactly why it's the right choice for screenshots, logos, and anything with flat colors or sharp text edges (lossy compression tends to create visible fuzz around sharp edges). PNG also supports a transparent background, which JPG cannot do at all. The cost is file size: a PNG photo is typically several times larger than the same photo as a JPG.
WebP was built specifically to beat both JPG and PNG at their own games — it supports both lossy and lossless modes, transparency, and typically produces files 25-35% smaller than an equivalent-quality JPG. Nearly every modern browser supports WebP natively, which is why it's increasingly the default output of image-editing and screenshot tools. The catch: some older desktop software, print workflows, and a few government/form-upload portals still only accept JPG or PNG, so you may need to convert a WebP image back before using it outside a browser.
HEIC (High Efficiency Image Container) is the default photo format on modern iPhones — it stores photos at roughly half the size of an equivalent JPG with no visible quality loss, which is great for saving storage on your phone. The problem shows up the moment you try to use that photo somewhere else: most Android devices, Windows programs, websites, and online forms either can't open a HEIC file at all or display a broken-image icon. Converting HEIC to JPG before uploading or sharing solves this instantly.
Conversion and compression both happen entirely inside your browser on this site — your photos are never uploaded to a server.