In effect from 17 October 2026

Privacy policy

MathPencil is free math lessons and calculators for learners of every age, published at mathpencil.com by HTPdevs. This policy explains what happens to information when the site is used. It states what is collected, what is not, and who else is involved.

The short version

• Your calculations never leave your browser. We do not receive them or store them.
• There is no account, no sign-up and no newsletter. We do not ask for your name or email.
• MathPencil sets no cookies of its own and saves nothing to your device.
• We run no analytics or tracking scripts of our own.
• Children use MathPencil, so ads are not personalised. Google is told to treat the site as child-directed, which turns off interest-based ads and remarketing.
• Advertising is served by Google, which still uses cookies and similar identifiers to show contextual ads, count them and prevent fraud. That is the only third party on the page.

What you key into the calculator

Both the keypad and the paste field are arithmetic running locally in your browser. The figures you key, the sums you paste and the tape they print are held in the page's memory for as long as the tab is open, and are discarded when you close or reload it. They are not transmitted to us, not written to your device, and not shared with anyone, including advertisers.

Cookies and local storage

MathPencil itself sets no cookies and writes nothing to local storage. Cookies you may find from this site come from Google's advertising, described next, or, in the European Economic Area, the United Kingdom and Switzerland, from the consent notice that records the choice you made.

Advertising

MathPencil is free to use and carries advertising to pay for its hosting and development. Ads are served by Google AdSense. MathPencil is used by children as well as adults, so the site is set up for Google to treat it as child-directed. Under that setting Google does not show interest-based ads or remarketing ads here, and the ads are chosen from the content of the page you are reading rather than from your browsing history. Google and its partners may still set or read cookies and similar identifiers to serve those ads, to limit how often you see the same one, to measure whether an ad worked, and to detect fraud.

Google's own description of how it uses information from sites that use its services is at policies.google.com/technologies/partner-sites. Google's controls for personalised advertising on other sites are at myadcenter.google.com, and you can opt out of personalisation by many other vendors at optout.aboutads.info or, in Europe, youronlinechoices.eu.

If you are in the EEA, the UK or Switzerland

Before any advertising cookie or identifier that requires consent is used, you are asked for that consent through a consent notice, and your choice is recorded and passed to Google and its partners. You can change it at any time through the notice. Where we and Google rely on consent, you may withdraw it; where information is handled for security and the basic operation of the site, the basis is our legitimate interest in keeping it running.

If you are in California or another US state

We do not sell personal information, and we do not share it for cross-context behavioural advertising: interest-based ads and remarketing are switched off on this site, as described above. We hold no account, profile or contact record about you that could be requested or deleted, because we never collect one.

Server logs

The web server that delivers the page keeps ordinary access logs: the IP address the request came from, the time, the page requested, the browser's user-agent string, and any errors. These are the standard records a web server keeps to stay secure and to diagnose faults. They are not used to build a profile of you, are not combined with anything else, and are rotated and deleted in the normal course of server maintenance.

Children

MathPencil is for learners of every age, and children use it. There is no account, no sign-up and no form that asks for a name or an email address, so the site does not collect personal information from anyone, of any age. Because children use the site, advertising is set to the child-directed treatment described above: no interest-based ads and no remarketing. If you are a parent or guardian and have a question about this, write to the address below.

Changes to this policy

If this policy changes in a way that matters, the date at the top of this page changes with it. The current version is always the one published here.

Getting in touch

Questions about privacy, or about anything else, go to support@htpdevs.com. There is more on the contact page.