Contact

Questions, corrections or a calculator you want us to build.

We read everything. Email hello@calclulo.com with a correction, a feature idea, a calculator request or a question about how a result was worked out. The more detail you give, the faster we can help.

Reporting a wrong result

Tell us which calculator, the values you entered and what you expected. A screenshot helps, and so does the link to the page, since many calculators have more than one mode. If you can, add how you worked out the figure you expected, because that shows us whether the formula, the rounding or an assumption is different. We will check the formula and fix it quickly.

Requesting a new calculator

Describe the problem you are trying to solve in a sentence or two, then list the inputs you would have and the answer you want. If a formula or a published source exists, such as a government guide, a textbook page or an industry standard, send the link. Two or three worked examples with the right answers let us test the tool before we publish it. We cannot build every request, but ideas that many people ask for, or that fill a gap in a category, move up the list.

Corrections to articles and facts

Each page has a written guide with examples, dates and facts. If you spot an error, a broken link or an out-of-date figure, such as a tax band, a customs rate or the date of an observance, tell us the page and what should change, and a link to the source if you have one. We prefer to correct a page than to leave a mistake in place.

Privacy and data questions

If you have a question about your data or privacy, write to the same address and say what you need. Our privacy policy explains what we collect and why, and our cookie policy lists the cookies. Please do not send passwords, card numbers or other sensitive details by email. We will never ask you for them.

Business, press and partnerships

For advertising, sponsorship, content partnerships, press questions or permission to use our material, write with the name of your organisation, what you have in mind and any dates that matter. If you want to use a calculator on your own site, tell us where, and we will let you know what is possible. Please do not copy our articles without permission.

What happens to your message

Messages are read by the people who build and edit the calculators. Reports about wrong results go to whoever looks after that category, and requests for new tools are collected in one list and reviewed together. We keep your email only to reply and to follow up on your report. If we need more detail, we will write back with a specific question, such as which units you used or which mode was selected. Sending a clear message the first time saves you waiting for a second round.

What we cannot help with

We cannot give personal financial, tax, legal or medical advice, and we cannot interpret a test result for you. If a calculator’s output worries you, see a qualified professional. We also cannot recover accounts on other platforms, such as TikTok, YouTube or Facebook, or answer questions about their payouts, although our calculators can help you estimate. If your question is about how to use a tool, check the questions at the bottom of its page first, because many are answered there.

Before you write

Thank you for taking the time to write. Every report makes the site better for the next person who uses it.