Eighteen Calculators, One Page
Percentage, VAT, discount, loan, compound interest, margin, tip, fuel, salary, unit price, savings, aspect ratio, average, ratio, proportion, percentage change, break-even and BMI.
Calculators
Percentage, VAT, discount, loan, margin and fourteen more
Eighteen everyday calculators that show their working
Web Tool
Official product page
Publisher:
POLPROG
Official product page
18
Calculators
7
Direct routes
10
Interface languages
0
Figures uploaded
01 / Calculators
About
Eighteen calculators sit behind one rail: percentage, VAT, discount, loan repayment, compound interest, margin and markup, tip, fuel cost, salary, unit price, savings goal, aspect ratio, average, ratio, proportion, percentage change, break-even and BMI. Picking one changes the panel, not the page.
The arithmetic is exact. Money is not held in floating point here: every value is scaled to an integer and computed with big integers, then rounded once, at the end. That is the difference between a VAT line that adds up and one that is a penny out for reasons nobody can explain, and between a loan schedule that closes at 0.00 and one that leaves a stray fraction on the last row.
Every result shows its formula. A number on its own cannot be checked, argued with or reused; the substituted expression underneath it can. Where a calculator has an assumption - which base a percentage change is measured from, whether a margin is on cost or on price - the assumption is written on the page rather than left implicit.
Nothing is sent anywhere. No figure you type reaches a server, the values live in the page address so a calculation can be sent as a link, and the seven most searched-for calculators have their own addresses so a search for "VAT calculator" lands on the VAT panel rather than on a list.
02 / Use case
What it solves
The problem
- Online calculators give a number and no way to check how it was reached.
- Floating point quietly makes money calculations a penny out, and nobody can say why.
- Every calculation means a different site, a different layout and a different set of adverts.
The outcome
- Eighteen calculators in one place, each showing the formula it used.
- Exact decimal arithmetic, so a VAT line and a loan schedule both add up.
- Nothing you type reaches a server. The values go into the page address so you can send a link to the calculation, and the only thing kept in this browser is your currency choice.
Who it is for
- Anyone working out VAT, a discount, a margin or a repayment.
- Freelancers and small businesses pricing work and checking invoices.
- Students and teachers who need the working shown, not just the answer.
03 / Key Features
Key Features
The most important capabilities, explained in practical terms.
Exact Decimal Arithmetic
Every currency figure is scaled to integers and computed with big integers, then rounded once at the end. No floating-point drift, and a loan schedule whose final balance is exactly zero. Solving for time in a savings goal needs a logarithm, so that one number is computed in double precision and the page says so beside it.
The Formula, Every Time
Each result is shown with the expression that produced it, with your own numbers substituted in, so it can be checked rather than trusted.
Stated Assumptions
Whether a margin is on cost or on price, which base a percentage change uses, how a repayment frequency names its periods - all written on the page rather than buried in a formula.
Amortisation Schedules
The loan calculator produces a full period-by-period schedule of interest, principal and remaining balance, named by the repayment frequency you chose.
Seven Direct Routes
Percentage, VAT, discount, loan, compound interest, margin and tip calculators each have their own page, opening straight onto that calculator.
Numbers the way you write them
1 234,56 in Warsaw, 1,234.56 in London, 1'234.50 in Zurich - all read as the same amount. Where one separator is genuinely ambiguous the page language decides, and the exact decimal arithmetic behind the result never sees a floating-point number.
VAT rates with a country on them
A bare 21% belongs to four countries at once. The presets carry the country code, and the field stays editable because rates change by legislation and reduced rates, exemptions and reverse charge are not on any preset list.
Compare, share, export
Pin one result and the next is shown beside it with the difference, which is how two loan offers get compared. Every calculation lives in its own link, and an amortisation schedule leaves as a CSV with all of its rows, not just the ones on screen.
04 / Download
Product access
A clear path from the official source to your first successful workflow.
Choose the right platform
Use one of the official links available for your device or browser.
Install or open
Follow the store instructions or open the web application. No third-party installers.
Configure and begin
Review the options, choose your preferences and start with the core workflow.
Official access options
05 / Technology
Technology behind the product
A transparent look at the core technologies used to build and maintain this product.
JavaScript
06 / Security
Privacy & Security
Your data stays on your device. Always.