Check whether a PNG has a transparent background, count fully and partially transparent pixels, and preview it on a checkerboard or solid colours.
Crop PNG, JPG and WebP images by dragging out a selection. 1:1 / 4:3 / 16:9 ratios and custom output sizes, with PNG transparency preserved.
Turn every page of a PDF into a PNG or JPG image. Pick 72 to 300 DPI, choose a page range, and multi-page exports are packed into a ZIP automatically. All local, nothing uploaded.
Combine several JPG, PNG or WebP images into one PDF in the order you choose. Drag to reorder, fit the page to the image or use A4 / Letter, and set margins and scaling. All local, nothing uploaded.
Images are the file type most likely to carry personal information: scans of ID cards and passport photos, pictures of a house with the number visible, unreleased design drafts, screenshots of private chats. A conventional online image tool has to upload all of that to a server and send it back — and you have no way to confirm how long the file sat on someone else's machine, whether a copy was kept, or whether it was fed into a model. The tools here do everything locally with the browser's own Canvas API, and keep working after you disconnect from the network once the page has loaded — that is a claim you can verify yourself, not a promise you have to take on faith.
Cropping is the step you reach for most often: a screenshot caught too much and the edges have to go, an avatar needs the middle square at 1:1, an illustration has to be 16:9 to line up with the layout. Transparency checking answers a different question — after you cut a subject out, a white background and a transparent one look identical in the preview, right up until you drop the image onto a dark slide and discover a white rectangle. The checker counts fully transparent and semi-transparent pixels and offers a checkerboard plus several solid-colour backdrops, so you can see the problem before you download.
Cropping supports PNG, JPG and WebP. PNG keeps its alpha channel; JPG has no transparency at the format level, so exports are filled with white. Transparency checking is PNG-only, because JPG simply has no alpha channel — the answer to "does this JPG have a transparent background" is always no. Neither tool caps the file size; the real limit is your device's memory.
These two are usually the two ends of one task: photos taken on a phone have to be bound, in order, into a single printable file — use Image to PDF; and the other way round, when the recipient only accepts images or you just want to drop a single page into a chat window, use PDF to Image to export pages as PNG or JPG. Their home category is PDF, but one end of each is always an image, which is why they are listed here as well. Neither direction costs you any quality: images go into the PDF byte-for-byte, and pages are re-rendered at the DPI you choose.
These pages are all adapted for mobile — open them in a phone browser, pick images from the camera roll and save the result straight back. The crop selection supports touch dragging and pinch zoom. If what you have is Markdown or a video, the site has categories for those too; the footer will take you there.