Calculators built around the rules that actually apply to you
HisaabHub is a set of free calculators and plain-English guides for people doing business or working in the UAE and Saudi Arabia. Each tool is built from the law or official guidance it relies on, shows its working, and lists its sources at the bottom of the page.
We focus on the questions that come with a deadline or a number attached: when e-invoicing becomes mandatory for your business, whether you need to register for VAT, how much corporate tax you owe, and what your end-of-service payment should be.
Why the dates matter now
The UAE’s e-invoicing system becomes mandatory in phases from 1 January 2027, Small Business Relief for corporate tax now runs to 2029, and VAT penalties changed in April 2026. Saudi Arabia continues to bring smaller businesses into Phase 2 of e-invoicing in waves. We update the affected calculators and guides when these rules change, and every page shows the date it was last checked.
Frequently asked questions
Are the calculators free?
Yes. There is no sign-up, and nothing you type into a calculator is stored or sent to us. The calculations run in your browser.
Can I rely on the results?
Use them as a well-founded estimate. They follow the published rules, but your own facts, such as a contract term or an unusual year end, can change the answer. For filings and disputes, confirm with the Federal Tax Authority, ZATCA, the relevant labour ministry or a registered adviser. Read how we calculate for the details.
Who writes the guides?
Our guides are researched and written by Ishaq Khokhar and checked against official sources. See About us and our editorial policy.
I found a mistake. What should I do?
Please tell us. We correct errors quickly and note significant corrections on the page.