Pay & Business Calculators

The numbers behind a payslip and a price

This shelf covers money from two directions that turn out to use the same arithmetic: what you get paid, and what a business charges. On the pay side, the Salary Calculator converts a rate of pay between hourly, daily, weekly, monthly and annual, the Take-Home Paycheck Calculator works out what actually lands in a US bank account after federal tax, Social Security and Medicare, and the Commission Calculator handles pay that depends on what gets sold. On the business side, the Margin Calculator sorts out the most expensive percentage mix-up in small-business pricing, and the Depreciation Calculator spreads an asset's cost across the years it is actually used. All five show their working in full, and every one of them is free.

Converting pay between periods without the four-week trap

Five figures describe the same pay from different angles: hourly, daily, weekly, monthly and annual. The Salary Calculator takes any one of them, plus your hours a week and the number of weeks a year you are actually paid for, and derives the rest. Its default working pattern, 40 hours a week for 52 weeks, gives 2,080 hours a year, the standard full-time year US payroll systems use to annualise an hourly wage.

The mistake it exists to catch is the weekly-times-four shortcut. A year has 52 weeks but only 12 months, so a month averages 4.33 weeks, not four. Multiply £800 a week by four and you guess £3,200 a month; the real figure, annual divided by 12, is £3,466.67, a gap of £266.67 every single month. The right route to a monthly figure always goes by way of the annual total. The tool also separates two questions people tend to blur: your hourly rate, which does not change when you take unpaid weeks, and your annual total, which does. Everything it produces is gross pay, deliberately, because take-home depends on the country and the tax year, and that job belongs to a calculator built for it.

From gross salary to what lands in the bank

The Take-Home Paycheck Calculator is that calculator, for pay taxed under the 2026 US federal system. It follows the same annualising logic real payroll uses: take one paycheck's taxable pay, scale it to a year, subtract the standard deduction for your filing status, run the result through the 2026 marginal brackets, then divide back down to a single payday. Alongside federal withholding it works out the two flat payroll taxes, Social Security at 6.2% of wages up to the $184,500 wage base for 2026, and Medicare at 1.45% with no ceiling plus the 0.9% Additional Medicare Tax withheld above $200,000 from a single employer.

Two details on that page repay attention. First, pay frequency: biweekly means 26 paychecks a year and semi-monthly means 24, so the same salary produces a slightly larger semi-monthly cheque, and they are not interchangeable labels. Second, pre-tax deductions behave differently from each other: a traditional 401(k) contribution reduces federal taxable pay but still counts as Social Security and Medicare wages, while a Section 125 health premium comes off before all three taxes. For the annual-liability version of the same tax, bracket by bracket, the Income Tax Calculator on the Tax shelf is the companion tool; and if the hours themselves are the unknown, the Hours Calculator adds up a working week before any pay maths starts.

Commission: flat, split and tiered

A flat commission is a percentage of a sale, and the Commission Calculator starts there: sale amount times rate, with an optional two-way split applied to the commission itself, never to the sale, so the shares always add back up to the full fee. It can also add a base salary to show combined earnings, a single-deal version of the on-target earnings figure quoted in sales job offers.

The part worth slowing down for is tiered commission, where the rate rises with revenue. Two genuinely different structures share that description. Marginal tiers pay each band's rate only on the revenue inside that band, exactly the way income tax brackets work. Cliff tiers pay one single rate on the entire revenue figure, whichever band it has reached, so crossing a threshold retroactively lifts everything already sold. On bands of 3% to £50,000, 5% to £100,000 and 8% above, £120,000 of revenue earns £5,600 under marginal tiers and £9,600 under cliff, nearly £4,000 apart from identical bands and identical sales. The calculator computes both side by side, because knowing which structure a comp plan actually uses matters more than the headline rates. As with everything on this shelf, commission figures are gross, before tax and other deductions.

Margin and markup are not the same percentage

Both margin and markup describe the same profit on the same sale; they differ only in what they divide it by. Margin divides profit by the selling price, markup divides it by the cost, and because the cost is the smaller number, markup is always the bigger percentage. A £10 cost sold for £15 is a 33.3% margin and a 50% markup at the same time. The Margin Calculator solves for any of cost, price or percentage from the other two, on either definition, and converts between the two with a live table.

The mix-up is expensive in one specific direction. Ask for "a 40% margin", apply a 40% markup instead, and a £10 cost gets priced at £14, which is only a 28.6% margin; the price a genuine 40% margin needs is £16.67, from the pricing-floor formula price = cost ÷ (1 − margin). Repeat that across a year of invoices and a business quietly under-prices everything it sells. One further trap the page flags: margin worked out from VAT-inclusive prices overstates the real profit, because the VAT was never the seller's money, so strip it out with the VAT Calculator first and bring the net figures back. A healthy gross margin still is not the whole story, and for whether an investment in the business pays off overall, the ROI Calculator asks the wider question.

Depreciation: spreading an asset's cost honestly

Buy a van or a machine and the cost is not really an expense of the day you bought it; it is consumed over the years the asset works. The Depreciation Calculator runs the same asset through the four textbook methods at once and charts all four book-value curves together. Straight-line spreads the depreciable amount evenly: a $50,000 asset with a $5,000 salvage value over five years loses exactly $9,000 a year. Declining balance front-loads by applying a fixed rate to the shrinking book value, $20,000 in year one on the same asset at a double-declining factor. Sum-of-the-years'-digits front-loads more gently through a counting-down fraction, and units of production ignores the calendar entirely and charges per mile driven or item made.

All four spread the same total; only the timing differs, and the right choice depends on how the asset actually loses usefulness. The page is equally clear about what it is not: tax authorities prescribe their own systems, MACRS in the US and capital allowances in the UK, so the textbook schedules here are for understanding and planning, not for a return.

Working a real problem across the shelf

The five tools chain together naturally. Someone weighing a job offer converts the quoted hourly rate to an annual figure with the Salary Calculator, then runs that salary through the Take-Home Paycheck Calculator to see a realistic payday, and if the role pays commission, checks whether the plan's tiers are marginal or cliff before believing the on-target number. Someone starting a small business goes the other way: the Margin Calculator sets prices against a real margin target rather than an accidental markup, the Depreciation Calculator spreads the kit across its working life, and the month-to-month plan for what the owner actually pays themselves belongs with the Budget Calculator over on the Spending shelf.

Questions people ask

Are these figures gross or take-home pay?

The Salary and Commission calculators produce gross figures, before tax and deductions, on purpose, because net pay depends on the country and the tax year. The Take-Home Paycheck Calculator is the one that models deductions, for US federal tax year 2026 specifically.

Why isn't a month just four weeks of pay?

Because 52 weeks divided by 12 months is 4.33 weeks per month. Multiplying weekly pay by four undershoots the true monthly figure by roughly a third of a week's pay every month, which adds up to about a full extra week's pay missed across a year.

What is the difference between margin and markup?

Margin measures profit against the selling price; markup measures the same profit against the cost. A 50% markup on a £10 cost gives a £15 price, which is only a 33.3% margin, and the two percentages should never be swapped when setting prices.

What is the difference between marginal and cliff commission tiers?

Marginal tiers pay each band's rate only on the revenue inside that band; cliff tiers pay the reached band's single rate on the whole revenue figure. The same revenue and the same bands can differ by thousands depending on which structure the plan uses.

Can I use the depreciation schedules on a tax return?

No. The calculator works the standard accounting methods, straight-line, declining balance, sum-of-the-years'-digits and units of production. Tax depreciation follows prescribed systems such as MACRS in the US or capital allowances in the UK, which have their own rates and tables.