Convert images between PNG, JPG, WebP and AVIF
Change an image's format without an install: PNG for transparency and sharp text, JPG for compatibility, WebP for a smaller web page, AVIF for smaller still. Convert one file or a batch, control the quality, and choose what happens to transparency when the target format can't carry it. The conversion runs in your browser and nothing is uploaded.
How to convert an image format
Add your images
Drop in one file or many — mixed formats in the same batch are fine.
Pick the output format
Choose PNG, JPG, WebP or AVIF, set the quality for the lossy ones, and pick a background colour if you're converting a transparent image to JPG.
Convert and download
Press Convert. A single file downloads directly; a batch arrives as a ZIP.
What Convert Image Format can do
Four formats
PNG, JPG, WebP and AVIF, in any direction.
Batch conversion
Convert a whole folder in one pass, with one setting.
Transparency handled
Choose the background colour when the target format has no alpha channel.
Local and unlimited
No upload, no file-count limit, no watermark.
Convert Image Format — frequently asked questions
Should I use WebP or AVIF for my website?
AVIF is smaller at the same quality; WebP is supported by slightly more of the long tail of old browsers and encodes faster. For most sites in 2026, AVIF with a WebP or JPG fallback is the right answer.
What happens to transparency when I convert a PNG to JPG?
JPG has no alpha channel, so transparent areas are filled with a solid colour. You choose which one — white by default.
Can I convert HEIC photos from my iPhone?
Only if your browser can decode HEIC, which Safari can and most others can't. If it fails, export the photo as JPG on the phone first and convert from there.
Do my images get uploaded to a server?
No. Every tool on Notoo Tools runs as JavaScript and WebAssembly inside your browser tab. There is no server that receives your files — you can disconnect from the network after the page loads and the tool keeps working.
Do I need an account or a subscription?
Neither. There's no sign-up, no email, no free-tier limit and no watermark. Bookmark the tool and it opens straight into the work.