A crowdfunding page has one job in the first two seconds: load and look credible. The photos carry that job — a campaign cover, a few story images, reward-tier mockups — and they are almost always straight off a phone at 4-8MB each. Every platform has a different ceiling, and hitting the wrong one is how uploads fail at 11pm the night before launch. GoFundMe takes JPEG/PNG/BMP under 20MB and wants at least 720x405, Givebutter recommends a 1200x630 cover with a 1MB cap, Donorbox caps a donation-form header at 692x550 and 1MB, and Kickstarter recommends 1024x576 with a 50MB ceiling. The ceilings are generous; the problem is what happens after upload — most platforms re-compress and resize, so a giant file gets softened twice and the campaign looks worse than the phone original. Skwish compresses and resizes in your browser with a live per-file size readout, so you can pre-size each image to the dimensions the platform actually renders, batch a whole launch folder, and export a ZIP. No server, no account, nothing uploaded.