OnlineConvertFree uploads your file to convert it: its free drop zone reads "100 MB maximum file size or Sign Up" and it has a paid tariff plan. A browser-based image converter runs on your own device with no size cap and no account, and nothing is uploaded.
OnlineConvertFree is an online converter, and its free drop zone states a 100 MB maximum file size before inviting you to sign up, with a paid tariff plan for more. That means your file is uploaded and the free tier is metered. A client-side image converter opens your picture in the browser and re-encodes it locally between PNG, JPG and WebP, so there is no size cap beyond your device memory and no account to create.
Local conversion wins when the image is private, when a file is larger than a fixed free cap, or when you do not want to sign up just to finish a basic task. OnlineConvertFree covers many more file types, so for unusual formats it may still be useful; for converting common web images, the free local route covers it without a plan.
No plan-based cap. Because conversion runs locally, size is bounded only by your device memory.
No. There is no account and no upsell to a paid tier.
No. The conversion happens in your browser, so the image never leaves your device.