Free · No sign-up · Instant results
Free calculators for dates, money, study and astrology
Momentix gives you 24 accurate online calculators – UK take-home pay, mortgage, VAT, age, percentages, savings, loans, BMI, grades and your Big Three – each with the formula, a worked example and clear steps.
- Dates & Time
- Percentages & Pricing
- Business & Freelance
- Savings & Loans
- Tax & Property
- Everyday & Health
- Learn & Play
- Study
- Astrology
24 free calculators · Works in your browser · Formulas and examples included
Popular tools
Everything you need to calculate
Start with a favourite, or browse the full collection.
Momentix at a glance
- 24Free toolsNew ones added regularly
- 9CategoriesFrom tax to astrology
- 0Sign-ups neededJust open and use
- 100%Calculated in your browserYour numbers stay with you
Why Momentix
Calculators you can trust and understand
Correct answers are only useful if you can see how they were reached.
Tested for accuracy
Every formula is covered by automated tests, including awkward edge cases like leap days, midnight shifts and 100% discounts.
Shows its working
Each result comes with the formula, the steps using your numbers and a worked example, so you can check and learn.
Private by design
Calculations run in your browser. No account, no sign-up and the numbers you enter are not stored on our servers.
Great on phones
Big tap targets, sensible keyboards and results that fit a small screen – built for quick use on the go.
Instant and free
No waiting, no paywall and no limits. Open a tool, enter your numbers and get an answer in seconds.
Charts and comparisons
Break-even lines, savings projections, loan balance curves and side-by-side schedules make numbers easy to understand.
On the way
Converters are coming soon
PDF tools, image converters and handy text utilities – free, fast and private, just like our calculators.
PDF Tools
Convert, combine and shrink PDFs without installing anything.
- PDF to WordSoon
- Word to PDFSoon
- Merge PDFSoon
- Split PDFSoon
- Compress PDFSoon
Image Converters
Switch formats and resize images in your browser.
- Image to PDFSoon
- JPG to PNGSoon
- PNG to JPGSoon
- Image CompressorSoon
- Image ResizerSoon
Text & Data
Small everyday utilities for writers and developers.
- Word CounterSoon
- Case ConverterSoon
- QR Code GeneratorSoon
- JSON FormatterSoon
Questions
Frequently Asked Questions (FAQs)
Yes. Every calculator is free to use with no account, no sign-up and no usage limits.
Each calculation uses a standard published formula and is covered by automated tests, including edge cases. Results are estimates for planning and learning – check important figures with an official source or a professional.
No. The numbers, dates and names you enter are processed in your browser and are not sent to our servers. The only exception is the city search in the Sun, Moon & Rising calculator, which sends the city name you type to a geocoding service.
Yes. Every page is designed for phones first, with a simple menu, large inputs and results that fit a small screen.
You can use 24 calculators across dates and time, percentages and pricing, business and freelance, savings and loans, tax and property, everyday and health, study, and astrology. Browse them all on the All Tools page.
We are building free PDF tools, image converters and small text utilities such as merging PDFs, converting JPG to PNG and counting words. They will appear in the Converters menu as soon as they are ready.