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Finance, health, math, science, unit conversion, business, food, sports, education, and daily planning. Every calculator includes the tool, formula notes, examples, FAQs, and related guides.

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Five calculator collections

Every calculator is organised into one of five topic areas. Click a collection to browse all the tools, sub-categories, and guides it contains.

Finance

137 calculators

Loans, mortgages, savings, investments, tax, budgets, retirement planning and more.

Finance
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Health & Fitness

385 calculators

BMI, calories, nutrition, body composition, fitness training, sports and wellbeing.

HealthSportsFood
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Science & Engineering

755 calculators

Physics, chemistry, construction, unit conversion, technology and technical design.

ConstructionConversionPhysicsChemistryEngineeringTechnology
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Business & Data

252 calculators

Profit margins, ROI, pricing, statistics, payroll, revenue and business planning.

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Everyday Life

491 calculators

Math, dates, discounts, tips, education, ecology and everyday household decisions.

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Calculator categories

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Finance

Plan loans, savings, investments, taxes, budgets, interest, and everyday money decisions with clear formulas and examples.

137 calculators

Health

Estimate health, fitness, nutrition, body measurements, and wellness metrics using practical reference formulas.

135 calculators

Math

Solve percentages, ratios, fractions, averages, geometry, algebra helpers, and common school or workplace math problems.

131 calculators

Construction

Estimate materials, areas, volumes, costs, paint, concrete, flooring, roofing, and renovation quantities.

130 calculators

Conversion

Convert units for length, weight, temperature, speed, volume, area, pressure, energy, and daily measurements.

125 calculators

Physics

Work with speed, force, energy, motion, electricity, waves, pressure, and classroom science formulas.

125 calculators

Chemistry

Use chemistry helpers for concentration, molarity, dilution, gas laws, molecular mass, and lab calculations.

125 calculators

Statistics

Analyze averages, probability, samples, confidence, variation, scores, and data interpretation problems.

125 calculators

Business

Estimate profit, margins, markup, inventory, payroll, pricing, revenue, productivity, and business planning metrics.

127 calculators

Everyday Life

Quick calculators for dates, time, tips, discounts, travel, fuel, recipes, shopping, and household planning.

110 calculators

Sports

Calculate pace, performance, training zones, scores, ratios, sports statistics, and fitness planning numbers.

125 calculators

Food

Scale recipes, estimate calories, cooking conversions, ingredient weights, nutrition, and meal planning quantities.

125 calculators

Ecology

Estimate energy use, water use, carbon footprint, recycling, transport impact, and sustainable living metrics.

125 calculators

Engineering

Work through mechanical, electrical, civil, and systems engineering formulas for practical design checks.

125 calculators

Education

Support learning with grade, score, GPA, reading, study time, classroom math, and academic planning calculators.

125 calculators

Technology

Estimate bandwidth, storage, download time, screen sizes, data transfer, battery life, and computing metrics.

125 calculators

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Finance and health calculators cover applicable legislation (CFPB, NHS, OSHA) and reference professional thresholds (e.g. debt-to-income ratios accepted by lenders, WHO BMI categories). Every page includes a disclaimer — these tools are planning aids. Consequential decisions should be reviewed with a qualified professional.

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Secondhand Savings Calculator

Free Secondhand Savings Calculator: quick secondhand savings calculator for everyday decisions. No signup needed.

A compound inflation calculator shows how the real purchasing power of money changes over time when prices rise at a compound annual rate. Unlike simple inflation calculations, compound inflation means each year's price rise is applied to the already-inflated previous year's price — making the long-run effect far larger than a simple multiplication of rate by years. At 3% annual inflation, 100 units of currency today becomes worth only 55 in real terms in 20 years. This is essential for retirement planning, salary negotiations, long-term contracts, and any financial projection extending more than a few years. and are important tools to use alongside inflation adjustment.

Central banks in most developed economies target 2% annual inflation. The 2021–2023 global inflation spike — driven by energy shocks and supply disruptions — demonstrated that long-run assumptions can be violated severely; many countries saw inflation peak above 8–11%. Inflation affects not just goods but assets: property prices, equity valuations, and bond yields all interact with inflation in complex ways.

  1. Enter the starting amount — the value of money, savings, or price you want to adjust.
  2. Enter the annual inflation rate. Use 2% for a developed-economy baseline, or the actual historical CPI rate from your country's official statistics office.
  3. Enter the number of years over which you want to project inflation.
  4. The result shows the equivalent nominal value in future years — what that amount will cost or be worth in future currency terms.
  5. To reverse the calculation (what is a future amount worth in today's money), use: present value = future value ÷ (1 + r)ⁿ.
  6. Run multiple scenarios at 1.5%, 2.5%, and 4% to understand how sensitive your plan is to the inflation assumption.

The compound inflation formula

Future value = Present value × (1 + r)ⁿ

Present value = Future value ÷ (1 + r)ⁿ

where r = annual inflation rate as a decimal (e.g. 0.03 for 3%), n = number of years.

The Rule of 70: years to halve purchasing power ≈ 70 ÷ inflation rate. At 2% inflation, purchasing power halves in ~35 years. At 7%, it halves in ~10 years.

Worked example: A salary of 50,000 today at 3% average inflation for 20 years. Future equivalent: 50,000 × 1.03²⁰ = 50,000 × 1.806 = 90,306. Your salary would need to be 90,306 in 20 years just to have the same purchasing power as 50,000 today.

Reading your inflation-adjusted result

Historical inflation benchmarks

Most developed economies averaged 2–3% annual inflation from 2000–2019, before the 2021–2023 spike. For long-run financial planning, 2–3% is the standard assumption, but sensitivity testing at 4–5% is prudent given recent experience. To find historical CPI data for your country, consult your national statistics office (ONS for UK, BLS for US, Eurostat for EU, ABS for Australia, Statistics Canada, etc.). The real value of any long-term financial target must account for this compounding erosion of purchasing power.

Everyday Life tips and best practices

Common mistakes to avoid

Inflation projections are mathematical estimates based on assumed future rates. Actual inflation depends on macroeconomic conditions, monetary policy, and global events. Official CPI data is published by each country's national statistics authority. Central bank inflation targets (typically 2%) are monetary policy objectives, not guarantees of future rates. Long-term financial contracts should specify whether monetary amounts are in nominal or real (inflation-indexed) terms. This tool is for illustrative and planning purposes only and does not constitute financial advice.