Retainer Calculator
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100 calls/day, no card, no spam. Built by one person, in public.
About Retainer
Retainer is a free, browser-based utility designed to make generating data on demand 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 generator suite covers most adjacent tasks with the same approach.
When you'd reach for Retainer
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.
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.
Frequently asked about Retainer
- Do I need to create an account to use Retainer?
- No. Retainer works without any signup. We only ask for an email if you decide to subscribe to a paid plan.
- Are my files uploaded to a server when I use Retainer?
- Retainer processes everything in your browser using local APIs. Your files never leave your device.
- Will Retainer change my original file?
- Never. Retainer only reads your input file and produces a new output file.
- Can I use Retainer commercially?
- Yes. The output of Retainer belongs entirely to you, with no licensing restrictions.
- What browsers does Retainer support?
- Every modern browser released in the last three years: Chrome, Firefox, Safari, Edge, Brave, Opera.