Formula: 1 mm of rain on 1 m2 = 1 liter of water
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100 calls/day, no card, no spam. Built by one person, in public.
About Rainfall
Rainfall is a free, browser-based utility designed to make this task as quick and frictionless as possible. The goal was to keep the path from "open the page" to "get the result" as short as possible. No mandatory account, no cookie wall, no upsell at every step. If you find yourself doing this regularly, the rest of the utility suite covers most adjacent tasks with the same approach.
When you'd reach for Rainfall
You need to handle a one-off task right before a meeting and don't have time to install anything.
Anyone working remotely on a borrowed or restricted machine.
Open the page, get the result, paste it into your doc — under a minute.
You're hitting the daily limit of a paid SaaS and need a backup option for a single quick job.
Marketers and ops people whose primary tool is metered.
Stay productive without burning credits.
You're on a public or shared machine and don't want to leave traces of what you're working on.
Travelers, contractors, anyone working from a friend's computer.
Nothing is uploaded, nothing persists if you're not signed in.
You're cleaning up a folder of files that accumulated over a project and need to standardize them.
Designers, writers, and developers wrapping up deliverables.
Drop each file in, copy the output, move on.
Frequently asked about Rainfall
- Can I use Rainfall commercially?
- Yes. The output of Rainfall belongs entirely to you, with no licensing restrictions.
- What browsers does Rainfall support?
- Every modern browser released in the last three years: Chrome, Firefox, Safari, Edge, Brave, Opera.
- Are my files uploaded to a server when I use Rainfall?
- Rainfall processes everything in your browser using local APIs. Your files never leave your device.
- Will Rainfall change my original file?
- Never. Rainfall only reads your input file and produces a new output file.
- Do I need to create an account to use Rainfall?
- No. Rainfall works without any signup. We only ask for an email if you decide to subscribe to a paid plan.