How We Calculate

Every calculator on this site is plain arithmetic on the numbers you enter. This page documents each formula and separates mathematics from assumptions. Intermediate values are never rounded; only displayed results are.

Arithmetic (always true)

• New pay = Current pay × (1 + Raise % ÷ 100)
• New pay = Current pay + Fixed raise
• Required raise % = ((Target − Current) ÷ Current) × 100
• Annual pay = Hourly rate × Hours per week × Paid weeks per year
• Gross change per paycheck = Annual change ÷ Pay periods (52, 26, 24, or 12)
• Offer net = (Base + Bonus + Retirement + Benefits) − (Health premium + Commute + Other costs)

Estimates that use your assumptions

• Estimated after deductions = Gross change × (1 − Deduction rate ÷ 100) — the deduction rate is a single effective percentage you enter; it is not a payroll or tax calculation.
• Real raise % = ((1 + Raise ÷ 100) ÷ (1 + Inflation ÷ 100) − 1) × 100 — the inflation rate is a value you enter, not live data. This site deliberately fetches nothing.
• Minimum nominal raise = ((1 + Desired real ÷ 100) × (1 + Inflation ÷ 100) − 1) × 100

Fixed conventions

• Five-year totals are simple sums (annual change × 5) with no compounding, further raises, or inflation applied.
• Daily pay figures assume a five-day working week.
• Semimonthly pay is annual ÷ 24; monthly is annual ÷ 12; biweekly is weekly × 2.

Data sources and versioning

The default inflation rate shown in the calculators is U.S. Bureau of Labor Statistics, CPI-U (all items, 12-month change) — as of July 2026. Source: https://www.bls.gov/news.release/cpi.nr0.htm.

The inflation rate is a default you can change on every calculator. This site never fetches live data at page load — the figure is a versioned value the editor updates, with its reference date shown — so results are fast, private, and reproducible. Always confirm the current figure at the source before relying on it.

Testing and corrections

The calculation engine is covered by an automated test suite that checks the PHP and JavaScript results against the same set of worked examples (percentage, fixed, target, hourly, all pay schedules, negative and edge cases). We run these tests before shipping a change. If you find a result you believe is wrong, please tell us through the contact page with the inputs you used.

Privacy of your numbers

Calculations run in your browser. Nothing you type is submitted, stored, or sent to any server. Share links place the values after the # symbol in the URL, which browsers do not transmit to the web server.

See a formula in use

Each formula above drives a specific tool. If you would rather see the arithmetic applied to real numbers than read it in the abstract, start with the calculator that matches your question:

• Salary Increase Calculator — new pay and the change per paycheck
• Raise Percentage Calculator — the percentage between two pay figures
• Salary to Hourly Calculator — annual pay divided across hours worked
• Hourly to Salary Calculator — an hourly rate annualised
• Cost of Living Raise Calculator — the real-raise ratio against inflation
• Job Offer Comparison Calculator — two offers totalled line by line

Longer explanations with worked examples are in the guides section. Our sourcing and correction rules are in the editorial policy, and you can report an error through the contact page.