Delisle To Celsius
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100 calls/day, no card, no spam. Built by one person, in public.
About De to C
Working with calculations no longer requires installing heavy desktop software — De to C runs entirely in your browser, instantly. 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 calculator tools that share the same philosophy: do one thing, do it well, get out of your way.
When you'd reach for De to C
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'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 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.
Frequently asked about De to C
- Will De to C change my original file?
- Never. De to C only reads your input file and produces a new output file.
- What browsers does De to C support?
- Every modern browser released in the last three years: Chrome, Firefox, Safari, Edge, Brave, Opera.
- Is De to C really free?
- Yes — De to C is free for unlimited personal use, with no account required and no watermark on the output.
- Are my files uploaded to a server when I use De to C?
- De to C processes everything in your browser using local APIs. Your files never leave your device.
- Do I need to create an account to use De to C?
- No. De to C works without any signup. We only ask for an email if you decide to subscribe to a paid plan.