1001 calculators. 250 of them free, forever.
Mortgage, income tax, VAT, loan EMI, BMI, concrete, macros, GPA — across 28 categories, with the working shown so you can check the answer. No account, no sign-in, no internet.
1001 Pro Calculators and Tools
The best all-in-one calculator app you will have: offline, no ads, and it doesn't collect any data.
Price a job, send the quote, work out anything, on your phone.
250 calculators free forever · Pro £0.99 a year, introductory · Trade Tools £9.99 once
CompareAgainst the apps it replacesMost calculator apps give you fifty tools and bury them in adverts. This one gives you 1001 and shows you none.
How it treats your data
It works offline.
There is no account, no sign-in and no server of its own. Every figure is worked out on the phone, so the app does exactly the same thing in flight mode as it does on full signal.
Nothing about you is sold.
No analytics, no tracking and no third party watching you use it. Your calculations never leave the device, so there is nothing to sell and nowhere for it to have gone.
There are no adverts.
The app carried advertising until August 2026. The library is out of the build entirely, along with every identifier and consent flow that came with it, on the free tier as well as Pro.
On a tablet
Two mortgage deals, side by side · Bricks for a wall, with the drawing beside the inputs
See it work
What it looks like
Trade Tools, bought once.
The instrument for a trade, in that trade's own notation: Construction, Plumbing, Electrical, HVAC, Machining, Welding, Automotive, Landscaping, Painting and Reference. 133 solvers, stairs and roofs drawn to scale, one purchase for all ten.
Quote a job in five minutes.
Itemised quotation, estimate or invoice on your own letterhead. Materials split from labour, tax at its rate, signature block. Out as a PDF, or straight into WhatsApp as an image.
Budgets and timesheets that end in a document.
A monthly budget that shows what could move, and a timesheet that runs from hours to take-home pay. Saved on the phone, and sent as a PDF, a spreadsheet or an image.
Nothing you type leaves the phone.
No adverts on either tier, no analytics, no crash reporting, no account. The app requests no permissions at all — not even internet.
How it compares
What each one does that the other does not, including where this app falls short.
Checked 2 October 2026.
Questions people ask
What is the best all-in-one calculator app?
If you want one that works offline, shows no adverts and collects no data, 1001 Pro Calculators and Tools puts 1,001 calculators in one app, across 28 categories, with every answer showing its working. 250 are free for good, there is no account, and nothing you type leaves your phone.
Is there a calculator app without ads?
Yes. 1001 Pro Calculators and Tools shows no adverts on any tier, free or Pro. The advertising library is not in the app at all, so there is nothing to switch off.
Does it work offline?
Yes, all of it. Every figure is worked out on the phone. There is no account, and the app does not even ask for internet access, so it works the same in flight mode as on full signal.
Is it an all-in-one calculator app?
It puts 1,001 calculators in one app, in 28 categories: mortgage and property, loans, tax and VAT, salary and work, business, health and fitness, home and construction, engineering, maths, conversions and more. Search by name or in plain words, such as “bmi” or “mortgage”, and every answer shows its working.
What is free, and what does Pro cost?
250 calculators are free for good, across all 28 categories, among them Percentage of a Number, Tip & Bill Split, Body Mass Index (BMI), Age, Loan Payment (EMI), Monthly Mortgage Payment, Compound Interest, Income Tax & Take-Home Pay, Brick Quantity and Bags of Concrete Needed. Pro opens all 1,001 and the worksheets: a 7-day free trial through Google Play or the App Store, then £0.99 for the first year and £2.99 a year after. Trade Tools are £9.99, once.
Is there a construction calculator app that works in feet and inches?
Yes. The Construction tools add and subtract feet and inches the way they are written on site, such as 12′ 7″ + 3′ 4½″, with metric alongside. They also cover stairs, roofs, layout and take-off, and the stairs are drawn to scale with every riser marked on the stringer.
Can it work out stairs, roof pitch, bricks and concrete?
Yes. Stair Rise, Run & Stringer and Roof Pitch & Rafter Length are Pro calculators, and Concrete Slab / Floor sizes a pour. Brick Quantity and Bags of Concrete Needed are two of the 250 free.
Are there plumbing, electrical and HVAC calculators?
Trade Tools cover Plumbing (pipe, offsets, flow, pressure, drainage), Electrical (cable, conduit fill, voltage drop, motors) and HVAC (ducts, airflow, superheat, subcooling), plus Machining, Welding, Automotive, Landscaping, Painting and Reference. That is 133 solvers in ten tool sets, for one purchase of £9.99 with a year of Pro included.
Can I write a quote or an invoice for a job?
Yes. Project makes a quotation, estimate or invoice on your own letterhead, with materials split from labour, tax at its rate and a signature block, and sends it as a PDF or as an image into WhatsApp. It is part of Pro.
Is there a timesheet and take-home pay calculator?
Timesheet runs from hours, breaks and overtime to tax, pension and take-home pay, and exports a signable PDF; it is part of Pro. Income Tax & Take-Home Pay is one of the 250 free calculators.
Can I plan a monthly budget?
Budget Planner lists what comes in and what goes out in a month, shows what is left or how far short you are, and picks out the spending that could move. It is saved on the phone and sent as a spreadsheet, a PDF statement or an image. It is part of Pro.
Can it compare two mortgages or show what overpaying saves?
Yes. Mortgage Deals Comparison puts two deals side by side, and Mortgage Overpayment Savings shows the interest saved and the years taken off. Both are Pro. Monthly Mortgage Payment is free.
Is it on iPhone?
Yes. It is on the App Store for iPhone and iPad, and on Google Play for Android.
What happens to what I type?
Nothing leaves the phone. There is no account, no analytics, no crash reporting and no tracking, so there is nothing to sell and nowhere for it to have gone.
How does it compare with other calculator and construction apps?
Most people end up with several apps: an all-in-one calculator, a construction calculator, one per trade, and something for quotes, timesheets and budgets, each often a subscription. This app does all of those in one, with no adverts and nothing sent anywhere, and its trade tools are £9.99 once. The comparison page also says where a dedicated app may suit you better.
The detail
- Free
- 250 calculators, forever, across all 28 categories. No account, no sign-in, and no advert on any tier.
- Trial
- 7 days with the whole product unlocked, Trade Tools included. The trial runs through the store, and cancelling before it ends means nothing is charged.
- Pro
- £0.99 a year — an introductory price, for a limited time. It is normally £2.99 a year. All 1001 calculators, every worksheet, and unlimited PDF and CSV export.
- Trade Tools
- £9.99, once. All ten tool sets, kept for good, with a year of Pro included. Nothing to renew.
Live now on Google Play and the App Store. 250 calculators free forever, no ads on any tier, and Pro is £0.99 for the first year.
Arithmetic, not advice. Rates and tax bands vary by country and change. Check anything you act on against the body that sets it.