Privacy Policy

Last updated: 24 September 2026

This Privacy Policy describes Our policies and procedures on the collection, use and disclosure of Your information when You use the Service and tells You about Your privacy rights and how the law protects You.

We use Your Personal Data to provide and improve the Service. By using the Service, You agree to the collection and use of information in accordance with this Privacy Policy.

The Short Version

MathCardo is a set of static pages, printable worksheets and games that run entirely in your browser. There is no account to create, nothing to sign up for, and no advertising. We do not set cookies ourselves and the games do not send anything anywhere: they are dealt from a data file that is downloaded with the page.

The site loads one third-party script, Google Analytics, which records page views anonymously to help us understand which worksheets are used. Google Analytics sets its own first-party cookies for this purpose and may use them across sites. You can opt out with the Google Analytics opt-out browser add-on, or by using a browser or extension that blocks the googletagmanager.com domain.

The only personal data we ever hold is what you choose to send us in an email, and the ordinary technical records that any web server keeps. The sections below set that out in full.

Interpretation And Definitions

Interpretation

The words of which the initial letter is capitalized have meanings defined under the following conditions. The following definitions shall have the same meaning regardless of whether they appear in singular or in plural.

Definitions

For the purposes of this Privacy Policy:

• Company (referred to as either “the Company”, “We”, “Us” or “Our” in this Agreement) refers to Wohok Solutions Limited, Room 1405, 135 Bonham Strand Trade Centre, 135 Bonham Strand, Sheung Wan, Hong Kong. For the purpose of the GDPR, the Company is the Data Controller.
• Cookies are small files that are placed on Your computer, mobile device or any other device by a website, containing the details of Your browsing history on that website among its many uses.
• Country refers to: Hong Kong SAR China.
• Data Controller, for the purposes of the GDPR (General Data Protection Regulation), refers to the Company as the legal person which alone or jointly with others determines the purposes and means of the processing of Personal Data.
• Device means any device that can access the Service such as a computer, a cellphone or a digital tablet.
• GDPR refers to EU General Data Protection Regulation.
• Personal Data is any information that relates to an identified or identifiable individual. For the purposes of GDPR, Personal Data means any information relating to You such as a name, an identification number, location data, online identifier or to one or more factors specific to the physical, physiological, genetic, mental, economic, cultural or social identity.
• Service refers to the Website.
• Service Provider means any natural or legal person who processes the data on behalf of the Company. It refers to third-party companies or individuals employed by the Company to facilitate the Service, to provide the Service on behalf of the Company, to perform services related to the Service or to assist the Company in analyzing how the Service is used.
• Usage Data refers to data collected automatically, either generated by the use of the Service or from the Service infrastructure itself (for example, the duration of a page visit).
• Website refers to MathCardo, accessible from https://mathcardo.com.
• You means the individual accessing or using the Service, or the company, or other legal entity on behalf of which such individual is accessing or using the Service, as applicable.

Collecting And Using Your Personal Data

Personal Data

We do not ask You for any Personal Data in order to use this website. There is no account, no registration, no newsletter and no contact form. You can read every page, download every worksheet and play every game without telling Us anything about Yourself.

The only Personal Data We hold is the Personal Data You choose to send Us. If You email Us, We will hold Your email address and whatever You write, for as long as is needed to answer You and to keep a record of the enquiry.

Usage Data

The Service is delivered by a web hosting provider. Like every web server, it records ordinary technical information about requests, which may include Your Internet Protocol address, the browser type and version, the pages of the Service that You visit, the time and date of Your visit and other diagnostic data. This is collected by the hosting infrastructure.

We use these records only to keep the Service running and secure, for example to investigate an outage or abuse. We do not use them to build a profile of You and We do not combine them with any other data.

In addition, the site loads Google Analytics on every page. It records page views and the general actions You take (for example, which worksheet You open), using the first-party analytics cookies described under Tracking Technologies And Cookies below. Google Analytics does not know who You are, and We have disabled advertising and demographics features, so the data Google sees is a list of page views against an anonymous browser identifier.

Tracking Technologies And Cookies

We do not set any cookies ourselves, and the games on this website do not set cookies either. There is one third-party script on every page - Google Analytics - and it is the only thing that writes cookies for this site.

Google Analytics sets the following cookies on Your device when You visit MathCardo, with the identifiers _ga and _ga_*:

• What they are. First-party cookies (set by the mathcardo.com domain itself) containing a randomly generated identifier for Your browser. The cookies let Google tell one visit from the next and report a page view count.
• What they contain. An identifier such as GA1.2.1234567890.1234567890 and an expiry timestamp. They do not contain Your name, email address, IP address or anything that identifies You to a person reading them.
• How long they last. _ga expires two years after Your last visit. _ga_* (the newer “analytics.js with cookie-less GA4 fallback” variant) expires two years after Your last visit. Both are deleted automatically by Your browser when they expire.
• What they are used for. Producing the aggregate counts We look at - how many people read each worksheet page, how many came from which country, and similar. Google may also use the identifier to recognise You across other sites that use Google Analytics, but We do not enable advertising features and the identifier alone cannot be used to identify You personally.
• The legal basis. Where this law requires a legal basis, We rely on Our legitimate interest in understanding which worksheets are used, on the understanding that the cookies set are cookies of the minimum-necessary kind and that a working opt-out is provided (see below).

Opting out

You can stop Google Analytics from collecting data on MathCardo in any of the following ways:

• Install Google’s Google Analytics opt-out browser add-on. It instructs the script to send a do-not-track flag, and We honour that flag.
• Use a browser, content blocker, or DNS-level blocker that filters requests to www.googletagmanager.com. With the script blocked, Google Analytics cannot run on the page and no analytics cookies are set on this site.
• Do not accept the cookie in Your browser when prompted. Google Analytics will still load, but the bounce will be recorded against a non-cookied session.
• Use Your browser’s privacy or “Send Do Not Track” setting. We also honour that signal.

Opting out does not affect any other part of MathCardo: every worksheet still downloads, every game still plays, every answer sheet still works.

The games on this website run entirely in Your browser and store nothing on Your device. Progress within a game lasts only as long as the page is open.

Our hosting provider may set strictly necessary cookies for security purposes, such as protecting the Service against automated attacks. Those are not under Our control and are not used to track You.

Children’s Privacy

MathCardo is used by children, and that is precisely why it tries to collect nothing that identifies them. There is no account, no login, no comment, no upload and no form of any kind, so a child cannot give Us Personal Data through this website. The worksheets are printable PDF files that You download and keep - downloading one tells Us nothing about who You are.

Google Analytics is the one exception, and it is intentionally limited. The identifier it sets is a random string tied to Your browser, not to a name, an email or a child’s identity. It expires after two years and We do not enable Google’s advertising or demographics features. It is allowed to run on pages that adults browse, and it can also run on pages that children reach because We have no way to tell the two apart. A parent or teacher who does not want this can use the steps under Opting out above: the same opt-out a parent applies at the browser level on a family device covers a child’s visit too.

We do not knowingly ask children for Personal Data and We do not allow other visitors to do so. If a child has emailed Us, a parent or guardian may write to the address at the bottom of this page and We will delete the message.

Use Of Your Personal Data

The Company may use Personal Data for the following purposes only:

• To reply to You. If You email Us, We use Your email address to answer You.
• To provide and maintain Our Service, including keeping it secure and available.
• To understand which worksheets are used. Aggregate, anonymised Google Analytics data (page views per worksheet, country-level counts, and the like) tells Us which topics and grades are most in demand, so We can decide which new topics to add. Advertising and demographic features are turned off, so Google does not build an advertising profile of You on Our behalf and We do not see anything more specific than the topic and the country. The opt-out under Tracking Technologies And Cookies stops this collection entirely.
• For the performance of a contract, where You have bought something from Us, so that We can deal with the sale and any problem with it.

We do not sell Your Personal Data, and We do not share it for advertising. We will only share it where We are required to by law, or with the Service Providers named below where that is necessary to run the Service.

Service Providers

A small number of third parties are involved in running MathCardo. Each of them receives only what it needs to do its job, and each is bound by its own privacy policy.

• Hosting. The website and the PDF files are served by a hosting provider (Cloudflare Pages), which necessarily processes the technical request data described above.
• Google Analytics. Every page loads the Google Analytics script from googletagmanager.com. Google receives Your IP address, the page URL, the country Your request came from, a random browser identifier cookie, and a timestamp. It does not receive Your name or email. Google’s privacy policy and how Google uses data from partner sites govern what it does with that data. Advertising and demographics reporting are turned off on MathCardo’s GA4 property.
• Gumroad. The optional classroom bundle is sold and delivered through Gumroad. If You buy it, You deal with Gumroad directly and Your payment details and email address are given to Gumroad, not to Us. Gumroad’s own privacy policy governs what it does with them. We receive only the information Gumroad gives sellers, such as an order notification.
• Social networks and WhatsApp. The sharing buttons on our pages are ordinary links. Nothing is sent to any social network until You click one, and then You are subject to that network’s own privacy policy.

Retention Of Your Personal Data

The Company will retain Your Personal Data only for as long as is necessary for the purposes set out in this Privacy Policy. An email enquiry is kept for as long as is needed to deal with it and to keep a record of what was agreed, and is then deleted.

Where required by law (such as tax and bookkeeping records) We keep the necessary records for the time the law specifies, and no longer.

Web-server access logs are retained only as long as is necessary for security and abuse handling, and are then rotated out. We do not enrich them with anything that identifies You and We do not share them with advertisers.

Google Analytics data is retained by Google on the rolling schedule set out in the Tracking Technologies And Cookies section above. The cookies expire at most two years after Your last visit, and Google’s own retention controls then govern how long the underlying event records are held. A copy of the page-URL and country counts is held by Us in Cloudflare’s Analytics Engine (Cloudflare-managed, retained for a short rolling window) and is not held past 14 months.

Transfer Of Your Personal Data

Your information, including Personal Data, is processed at the Company’s operating offices and in any other places where the parties involved in the processing are located. It means that this information may be transferred to — and maintained on — computers located outside of Your state, province, country or other governmental jurisdiction where the data protection laws may differ than those from Your jurisdiction.

Your consent to this Privacy Policy followed by Your submission of such information represents Your agreement to that transfer.

The Company will take all steps reasonably necessary to ensure that Your data is treated securely and in accordance with this Privacy Policy and no transfer of Your Personal Data will take place to an organization or a country unless there are adequate controls in place including the security of Your data and other personal information.

Delete Your Personal Data

You have the right to delete or request that We assist in deleting the Personal Data that We have collected about You.

The Personal Data We hold directly is the Personal Data You sent Us by email. You can ask Us to delete any individual email at any time by writing to [email protected] and We will do so. Please note, however, that We may need to retain certain information when We have a legal obligation or lawful basis to do so (for example, an invoice We are required to keep for tax purposes).

For the data that lives elsewhere (the Google Analytics identifier cookie, and the aggregate, non-personal records in Cloudflare’s logs), You can delete it yourself by clearing Your browser’s cookies for mathcardo.com, or via the Opting out steps above. Once Your browser no longer holds the identifier, the page views that were tied to it are not tied to You as a person; the rest of the aggregate counts are unaffected.

Disclosure Of Your Personal Data

Business Transactions

If the Company is involved in a merger, acquisition or asset sale, Your Personal Data may be transferred. We will provide notice before Your Personal Data is transferred and becomes subject to a different Privacy Policy.

Law Enforcement

Under certain circumstances, the Company may be required to disclose Your Personal Data if required to do so by law or in response to valid requests by public authorities (e.g. a court or a government agency).

Other Legal Requirements

The Company may disclose Your Personal Data in the good faith belief that such action is necessary to:

• comply with a legal obligation;
• protect and defend the rights or property of the Company;
• prevent or investigate possible wrongdoing in connection with the Service;
• protect the personal safety of Users of the Service or the public;
• protect against legal liability.

Security Of Your Personal Data

The security of Your Personal Data is important to Us, but remember that no method of transmission over the Internet, or method of electronic storage is 100% secure. While We strive to use commercially acceptable means to protect Your Personal Data, We cannot guarantee its absolute security.

Your Rights Under The GDPR

If You are within the European Union, You have the right to access, correct, delete or restrict the processing of Your Personal Data, the right to object to processing, the right to data portability, and the right to withdraw consent where processing is based on consent.

Emails You send Us. You can have that email and Our replies deleted by writing to [email protected]. We hold no other Personal Data about You as a Company.

Google Analytics cookies. You can opt out of the cookies described above in one click by clicking this link, installing Google’s opt-out add-on, or using a browser/content blocker. Clearing the cookies for mathcardo.com from Your browser also removes the identifier stored there. The aggregate, non-personal event records held by Google and by Cloudflare’s logs are not associated with You personally, so the right to erasure does not require a separate step against them, but You can write to Us and We will raise it with the processors involved.

To exercise any of these rights, write to [email protected]. You also have the right to complain to Your local data protection authority.

Our lawful basis for processing an email You send Us is Our legitimate interest in answering it, and, where You have bought something, the performance of a contract. Our lawful basis for the Google Analytics cookies is Our legitimate interest in understanding which worksheets are most used, with the minimum-necessary cookies and a working opt-out as safeguards.

Your Rights Under The CCPA/CPRA

If You are a California resident, You have the right to know what Personal Data is collected, to request its deletion, and to opt out of the sale or sharing of Personal Data.

We do not sell Personal Data, and We do not share it for cross-context behavioural advertising. The Google Analytics data described above is used only to count page views on MathCardo. We have not turned on Google Analytics’s “advertising features” (audiences, demographics, interests), so no segment of Your activity is exported to advertisers.

Personal Data We hold directly: the email You sent Us. Personal Data held by Our processors on Our behalf: the Google Analytics identifier cookie described above. Across a rolling 12-month window We do not sell or share either of these for any commercial purpose.

To make a request, write to [email protected]. We will respond within 45 days as required by California law.

Links To Other Websites

Our Service may contain links to other websites that are not operated by Us, such as the payment page on Gumroad. If You click on a third party link, You will be directed to that third party’s site. We strongly advise You to review the Privacy Policy of every site You visit.

We have no control over and assume no responsibility for the content, privacy policies or practices of any third party sites or services.

Changes To This Privacy Policy

We may update Our Privacy Policy from time to time. We will notify You of any changes by posting the new Privacy Policy on this page and updating the “Last updated” date at the top.

You are advised to review this Privacy Policy periodically for any changes. Changes to this Privacy Policy are effective when they are posted on this page.

Contact Us

If you have any questions about this Privacy Policy, you can contact us at [email protected].