Correlation Calc
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100 calls/day, no card, no spam. Built by one person, in public.
About Correlation
Correlation is a free, browser-based utility designed to make this task as quick and frictionless as possible. Everything happens client-side, which means your files and data never leave your machine. The interface is intentionally minimal so you can focus on the task instead of learning the tool. It is one of about a hundred utility tools that share the same philosophy: do one thing, do it well, get out of your way.
When you'd reach for Correlation
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 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 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.
Frequently asked about Correlation
- What browsers does Correlation support?
- Every modern browser released in the last three years: Chrome, Firefox, Safari, Edge, Brave, Opera.
- Is Correlation really free?
- Yes — Correlation is free for unlimited personal use, with no account required and no watermark on the output.
- Can I use Correlation commercially?
- Yes. The output of Correlation belongs entirely to you, with no licensing restrictions.
- Will Correlation change my original file?
- Never. Correlation only reads your input file and produces a new output file.
- Do I need to create an account to use Correlation?
- No. Correlation works without any signup. We only ask for an email if you decide to subscribe to a paid plan.