Last updated: 6 October 2026
1. Who we are
Simply Calculated is run by Kuda Mativenga, an individual based in the United Kingdom. For this website, Kuda Mativenga is the “controller” of your personal data under UK data protection law (the UK GDPR and the Data Protection Act 2018).
Contact: [email protected]
2. What our tools do
Simply Calculated offers free calculators and checkers for UK money questions, such as tax, pay, VAT, business figures and borrowing. The site is being built: until a tool is live, this policy describes how it will work when it launches.
Our calculators, the IBAN checker and the invoice generator work in your own web browser. What you type into them stays on your device and is not sent to us.
That includes the corporation tax, dividend tax, salary sacrifice, inheritance tax, loan repayment, credit card repayment and PCP car finance calculators: they run in your browser, and nothing you type into them is sent to us or stored.
3. The VAT number checker
The VAT number checker (coming soon) tells you whether a VAT registration number is valid and who it belongs to. To do that, it has to ask the official registers:
- UK numbers (starting GB): the number you enter is sent from our server to HM Revenue & Customs (HMRC) through its “Check a UK VAT number” service.
- EU numbers, and Northern Ireland numbers starting XI: the number you enter is sent from our server to the European Commission’s VAT Information Exchange System (VIES).
For a normal check, we send only the VAT number you want to check. HMRC or VIES tells us whether it is valid and, where available, the registered business name and address. We show you that result on screen.
If you ask for proof of a check, we also send your own VAT number along with the number you are checking: to HMRC for UK numbers, or to VIES for EU and XI numbers. HMRC or VIES then returns a reference number for the check, which you can keep as evidence that you checked the number. We show you this reference number on screen and do not keep it, or your VAT number. If you download the proof as a PDF, the PDF is made in your browser and is not sent to us.
If the business is a sole trader, the name and address returned may be personal data about that person. It comes from the official public register. We use it only to show you the result of your check.
Limiting checks. To stop the checker being misused, and to keep within the limits HMRC and VIES set, each visitor can make up to 20 checks in 10 minutes. To count checks, our server turns your IP address into a scrambled code that can’t be turned back into the address, using a key that exists only in memory. The code and the times of your checks are held in memory for up to 10 minutes, then deleted. They are never written to storage, and are never linked to the numbers you check.
HMRC and the European Commission are responsible for their own records and their handling of the request. See HMRC’s personal information charter and the VIES website.
Why we can do this (lawful basis): legitimate interests. You asked us to check a number, or to get proof of a check, and we need to send the number or numbers to the register to answer. Limiting checks protects the service for everyone.
4. The invoice generator
The invoice generator makes your invoice and its PDF entirely in your browser. Nothing you type, and no logo or signature you add or draw, is sent to us. If you invoice in another currency, you type in the exchange rate yourself: the site doesn’t fetch exchange rates or anything else.
“Remember my details on this device” is optional and off until you tick it. If you tick it, your browser’s local storage keeps:
- your own business details: name, address, email, phone, website, your own name, VAT number and company or SIREN number
- how to pay you: account name, sort code, account number, IBAN, BIC or SWIFT code, bank name and branch code
- where your business is, the currency you use and, if you chose “Another country”, your tax name and main rate
- your usual invoice type, payment terms and, for France, your late payment terms
- the invoice colour you chose
- the last invoice number you downloaded, so we can suggest the next one
- your logo and your signature, but only if each is under 300 KB
It never keeps your customers’ details, what you charged for, discounts, amounts paid, exchange rates or the invoices themselves. This information stays on your device. We can’t see it, and it is never sent to us.
To remove all of it, including your logo and signature, click Forget my details on the invoice generator, untick the box, or clear your browser’s site data. If the customer’s VAT number check is switched on, that check works as described in section 3.
5. What we keep, and what we don’t
- No account is needed. We don’t ask for your name, email or any login to use the tools.
- We don’t keep the numbers you check, your own VAT number if you ask for proof of a check, or the results and reference numbers. The check is passed to HMRC or VIES and the answer is shown to you; we do not store any of it in a database or in our own logs.
- We don’t sell or share your data for marketing.
6. Hosting and Cloudflare’s logs
The site is hosted on Cloudflare Pages, run by Cloudflare, Inc. Like any website host, Cloudflare processes technical information about each visit so that it can deliver the pages and protect the site from attacks. This includes your IP address, the page requested, the time, and your browser type. Cloudflare acts as our “processor” for this information.
On how long this is kept, Cloudflare states that it processes this log data “on behalf of our customers in our data centers in the U.S. and Europe for a limited period of time” (Cloudflare GDPR FAQ). Its privacy policy (effective 4 November 2025) does not give a fixed number of days. It says data is deleted when its retention period ends, and that the period depends on the purpose and on legal obligations.
On the free plan we use, we can see only totals, such as the number of page views. We cannot see or download individual visitors’ IP addresses. Because Cloudflare may process data in the United States, it relies on the international transfer safeguards described in its privacy policy.
7. Cookies, local storage and analytics
We don’t use cookies today. We don’t set any cookies, and we don’t use similar technologies such as local storage to track you. The only thing we put in local storage is the invoice generator’s “Remember my details” information, and only if you ask for it (section 4).
To count visits we use Cloudflare Web Analytics, which is cookie-free. According to Cloudflare, it “does not use any client-side state, such as cookies or localStorage”. It does not track individual visitors over time by IP address or “fingerprinting”. It shows us totals such as page views, the pages people visit, the referring site, and page loading speed.
8. Advertising in future
We may show adverts from Google AdSense in future to keep the tools free. Google AdSense can use cookies. Before any adverts appear, we will update this policy and add a consent banner, so that you can choose whether to allow advertising cookies.
9. If you email us
If you email us, we use your email address and message only to reply. Our lawful basis is legitimate interests. We keep the email only as long as we need to deal with your question, and normally delete it within 12 months.
10. Your rights and how to complain
Under the UK GDPR you have the right to:
- ask for a copy of the personal data we hold about you (right of access)
- ask us to correct it (rectification) or delete it (erasure)
- ask us to limit how we use it (restriction), or object to our use of it
- receive it in a portable format, where that applies
Because we don’t keep the numbers you check and have no accounts, we usually hold no personal data about visitors beyond any emails you send us. To use any of these rights, email [email protected]. We will reply within one month.
If you are unhappy with how we handle your data, please tell us first. You also have the right to complain to the Information Commissioner’s Office (ICO), the UK data protection regulator: ico.org.uk/make-a-complaint or 0303 123 1113.
11. Security
The site is served only over an encrypted connection (HTTPS). Any keys we use to connect to HMRC are kept on our server and are never sent to your browser.
To report a security problem or a suspected data breach, email [email protected] with “Security report” in the subject. We act on reports promptly. If personal data is affected, we will tell the ICO, and HMRC where relevant, within 72 hours of becoming aware of it.
12. Changes to this policy
We will update this page when the way we handle data changes, for example when a new tool goes live or before any advertising starts. The date at the top shows the latest version.