# The Online Calculator 24 > The Online Calculator 24 is a calculator platform with 3602 fully working calculators across 20 categories, covering finance, health, real estate, business, technology, science and everyday life. Every page states its formula, shows the worked steps and names its source. The Online Calculator 24 publishes in stages: 3602 calculators are live now and the library grows by 100 every 3 days, most-searchable first. Content is in English with US conventions as the default and metric/UK-EU variants where the difference matters. ## Structure - Home & search: / (instant search across the live library) - Categories index: /categories - Live calculators index: /popular - General-purpose calculator: /general-calculator - Category page: /{category-slug} - Subcategory page: /{category-slug}/{subcategory-slug} - Calculator page: /{category-slug}/{subcategory-slug}/{calculator-slug} - Calculator embed (chrome-less iframe): /{category-slug}/{subcategory-slug}/{calculator-slug}?embed=1 - Open compute API docs: /api - Compute any engine as JSON: /api/calculate?slug={calculator-slug}&{field}={value} - Full machine-readable index of every live calculator: /llms-full.txt - XML sitemap index: /sitemap.xml ## Categories (20) - Finance & Banking: /finance-banking (350 live pages) - Business & Entrepreneurship: /business-entrepreneurship (304 live pages) - Health & Medical: /health-medical (259 live pages) - Investing & Markets: /investing-markets (250 live pages) - Fitness & Sports: /fitness-sports (248 live pages) - Technology & Computing: /technology-computing (201 live pages) - Arts, Music & Creative: /arts-music-creative (200 live pages) - Real Estate & Property: /real-estate-property (199 live pages) - Miscellaneous & Fun: /miscellaneous-fun (196 live pages) - Science & Research: /science-research (153 live pages) - Construction & Home Improvement: /construction-home-improvement (152 live pages) - Cooking & Food Science: /cooking-food-science (151 live pages) - Legal & Law: /legal-law (149 live pages) - Education & Academics: /education-academics (148 live pages) - Environmental & Sustainability: /environmental-sustainability (148 live pages) - Agriculture & Farming: /agriculture-farming (100 live pages) - Personal Development & Productivity: /personal-development-productivity (100 live pages) - Astronomy & Space Science: /astronomy-space-science (98 live pages) - Retirement Planning: /retirement-planning (98 live pages) - Travel & Transportation: /travel-transportation (98 live pages) ## Starting points ### Finance & Banking - [Personal Loan Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/personal-loan-calculator) - [Car Loan Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/car-loan-calculator) - [Mortgage Payment Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/mortgage-calculator) - [Student Loan Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/student-loan-calculator) - [Business Loan Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/business-loan-calculator) - [Payday Loan Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/payday-loan-calculator) - [Boat Loan Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/boat-loan-calculator) - [RV Loan Calculator](https://tools.calculators24.com/finance-banking/loans-mortgages/rv-loan-calculator) ### Business & Entrepreneurship - [Startup Valuation, Funding Round & Dilution Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/startup-valuation-calculator) - [Pre-Money Valuation Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/pre-money-valuation-calculator) - [Post-Money Valuation Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/post-money-valuation-calculator) - [Dilution Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/dilution-calculator-calculator) - [Startup Capitalization Table & Equity Dilution Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/cap-table-calculator) - [Option Pool Shuffle Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/option-pool-shuffle-calculator) - [SAFE Note Conversion Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/safe-note-conversion-calculator) - [Convertible Note Conversion Calculator](https://tools.calculators24.com/business-entrepreneurship/startup-metrics/convertible-note-conversion-calculator) ### Health & Medical - [BMI Calculator](https://tools.calculators24.com/health-medical/body-measurements/bmi-calculator) - [US Navy Body Fat & Lean Body Mass Calculator](https://tools.calculators24.com/health-medical/body-measurements/body-fat-navy-method-calculator) - [Body Fat (Skinfold) Calculator](https://tools.calculators24.com/health-medical/body-measurements/body-fat-skinfold-calculator) - [Body Fat (BIA) Calculator](https://tools.calculators24.com/health-medical/body-measurements/body-fat-bia-calculator) - [Body Fat (DEXA Estimate) Calculator](https://tools.calculators24.com/health-medical/body-measurements/body-fat-dexa-estimate-calculator) - [Lean Body Mass Calculator](https://tools.calculators24.com/health-medical/body-measurements/lean-body-mass-calculator) - [Fat Mass Calculator](https://tools.calculators24.com/health-medical/body-measurements/fat-mass-calculator) - [Bone Mass Estimate Calculator](https://tools.calculators24.com/health-medical/body-measurements/bone-mass-estimate-calculator) ### Investing & Markets - [Stock Total Return & CAGR Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/stock-return-calculator) - [Dividend Yield Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/dividend-yield-calculator) - [Dividend Discount Model (Gordon Growth) Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/dividend-growth-calculator) - [Payout Ratio Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/payout-ratio-calculator) - [Earnings Per Share Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/earnings-per-share-calculator) - [P/E Ratio Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/p-e-ratio-calculator) - [Forward P/E Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/forward-p-e-calculator) - [PEG Ratio Calculator](https://tools.calculators24.com/investing-markets/stocks-equities/peg-ratio-calculator) ### Fitness & Sports - [5K Pace, Splits & Race Strategy Calculator](https://tools.calculators24.com/fitness-sports/running/5k-pace-calculator) - [10K Pace Calculator](https://tools.calculators24.com/fitness-sports/running/10k-pace-calculator) - [Half Marathon Pace Calculator](https://tools.calculators24.com/fitness-sports/running/half-marathon-pace-calculator) - [Marathon Pace Calculator](https://tools.calculators24.com/fitness-sports/running/marathon-pace-calculator) - [Ultra Marathon Pace Calculator](https://tools.calculators24.com/fitness-sports/running/ultra-marathon-pace-calculator) - [Race Predictor (Riegel) Calculator](https://tools.calculators24.com/fitness-sports/running/race-predictor-riegel-calculator) - [Pete Riegel Race Time Predictor Calculator](https://tools.calculators24.com/fitness-sports/running/race-predictor-pete-riegel-calculator) - [Jack Daniels VDOT Calculator](https://tools.calculators24.com/fitness-sports/running/jack-daniels-vdot-calculator) ### Technology & Computing - [Bandwidth Calculator](https://tools.calculators24.com/technology-computing/networks-storage/bandwidth-calculator) - [Download Time Calculator](https://tools.calculators24.com/technology-computing/networks-storage/download-time-calculator) - [Upload Time Calculator](https://tools.calculators24.com/technology-computing/networks-storage/upload-time-calculator) - [Latency Calculator](https://tools.calculators24.com/technology-computing/networks-storage/latency-calculator) - [Ping Calculator](https://tools.calculators24.com/technology-computing/networks-storage/ping-calculator) - [Jitter Calculator](https://tools.calculators24.com/technology-computing/networks-storage/jitter-calculator) - [Packet Loss Impact Calculator](https://tools.calculators24.com/technology-computing/networks-storage/packet-loss-impact-calculator) - [Throughput Calculator](https://tools.calculators24.com/technology-computing/networks-storage/throughput-calculator-2) ### Arts, Music & Creative - [BPM to Milliseconds Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/bpm-to-milliseconds-calculator) - [Note Duration Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/note-duration-calculator) - [Time Signature Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/time-signature-calculator) - [Tempo Change Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/tempo-change-calculator) - [Key Signature Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/key-signature-calculator) - [Interval Calculator Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/interval-calculator-calculator) - [Chord Frequency Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/chord-frequency-calculator) - [Harmonic Series Calculator](https://tools.calculators24.com/arts-music-creative/music-theory-production/harmonic-series-calculator) ### Real Estate & Property - [Home Affordability & DTI Underwriting Calculator](https://tools.calculators24.com/real-estate-property/home-buying/home-affordability-calculator) - [Maximum Purchase Price Calculator](https://tools.calculators24.com/real-estate-property/home-buying/maximum-purchase-price-calculator) - [Debt-to-Income for Home Calculator](https://tools.calculators24.com/real-estate-property/home-buying/debt-to-income-for-home-calculator) - [Down Payment Required Calculator](https://tools.calculators24.com/real-estate-property/home-buying/down-payment-required-calculator) - [Down Payment Savings Timeline Calculator](https://tools.calculators24.com/real-estate-property/home-buying/down-payment-savings-timeline-calculator) - [Itemized Buyer Closing Cost & Settlement Calculator](https://tools.calculators24.com/real-estate-property/home-buying/closing-cost-estimate-calculator) - [Title Insurance Cost Calculator](https://tools.calculators24.com/real-estate-property/home-buying/title-insurance-cost-calculator) - [Homeowner's Insurance Calculator](https://tools.calculators24.com/real-estate-property/home-buying/homeowner-s-insurance-calculator) ### Miscellaneous & Fun - [Age in Years Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/age-in-years-calculator) - [Age in Months Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/age-in-months-calculator) - [Age in Weeks Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/age-in-weeks-calculator) - [Age in Days Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/age-in-days-calculator) - [Age in Hours Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/age-in-hours-calculator) - [Age in Minutes Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/age-in-minutes-calculator) - [Age in Seconds Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/age-in-seconds-calculator) - [Days Between Dates Calculator](https://tools.calculators24.com/miscellaneous-fun/dates-time/days-between-dates-calculator) ### Science & Research - [A/B Test & Statistical Sample Size Calculator](https://tools.calculators24.com/science-research/statistics-data-science/sample-size-calculator) - [Statistical Power Calculator](https://tools.calculators24.com/science-research/statistics-data-science/statistical-power-calculator-2) - [Effect Size (Cohen's d) Calculator](https://tools.calculators24.com/science-research/statistics-data-science/effect-size-cohen-s-d-calculator) - [Effect Size (r) Calculator](https://tools.calculators24.com/science-research/statistics-data-science/effect-size-r-calculator) - [Effect Size (f) Calculator](https://tools.calculators24.com/science-research/statistics-data-science/effect-size-f-calculator) - [Confidence Interval (Mean) Calculator](https://tools.calculators24.com/science-research/statistics-data-science/confidence-interval-mean-calculator) - [Confidence Interval (Proportion) Calculator](https://tools.calculators24.com/science-research/statistics-data-science/confidence-interval-proportion-calculator) - [Margin of Error Calculator](https://tools.calculators24.com/science-research/statistics-data-science/margin-of-error-calculator) ### Construction & Home Improvement - [Concrete Volume Calculator](https://tools.calculators24.com/construction-home-improvement/materials/concrete-volume-calculator) - [Concrete Mix Ratio Calculator](https://tools.calculators24.com/construction-home-improvement/materials/concrete-mix-ratio-calculator) - [Cement Bags Calculator](https://tools.calculators24.com/construction-home-improvement/materials/cement-bags-calculator) - [Sand Volume Calculator](https://tools.calculators24.com/construction-home-improvement/materials/sand-volume-calculator) - [Gravel Volume Calculator](https://tools.calculators24.com/construction-home-improvement/materials/gravel-volume-calculator) - [Rebar Weight Calculator](https://tools.calculators24.com/construction-home-improvement/materials/rebar-weight-calculator) - [Steel Beam Weight Calculator](https://tools.calculators24.com/construction-home-improvement/materials/steel-beam-weight-calculator) - [Steel Plate Weight Calculator](https://tools.calculators24.com/construction-home-improvement/materials/steel-plate-weight-calculator) ### Cooking & Food Science - [Baker's Percentage Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/baker-s-percentage-calculator) - [Dough Hydration Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/dough-hydration-calculator) - [Flour Protein Impact Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/flour-protein-impact-calculator) - [Gluten Development Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/gluten-development-calculator) - [Yeast Quantity Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/yeast-quantity-calculator) - [Wild Yeast Ratio Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/wild-yeast-ratio-calculator) - [Sourdough Starter Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/sourdough-starter-calculator) - [Sourdough Hydration Calculator](https://tools.calculators24.com/cooking-food-science/baking-science/sourdough-hydration-calculator) ### Legal & Law - [Attorney Hourly Rate Calculator](https://tools.calculators24.com/legal-law/personal-legal/attorney-hourly-rate-calculator) - [Contingency Fee Calculator](https://tools.calculators24.com/legal-law/personal-legal/contingency-fee-calculator) - [Flat Fee vs Hourly Calculator](https://tools.calculators24.com/legal-law/personal-legal/flat-fee-vs-hourly-calculator) - [Retainer Cost Calculator](https://tools.calculators24.com/legal-law/personal-legal/retainer-cost-calculator) - [Legal Aid Eligibility Calculator](https://tools.calculators24.com/legal-law/personal-legal/legal-aid-eligibility-calculator) - [Pro Bono Value Calculator](https://tools.calculators24.com/legal-law/personal-legal/pro-bono-value-calculator) - [Small Claims Limit Calculator](https://tools.calculators24.com/legal-law/personal-legal/small-claims-limit-calculator) - [Filing Fee Calculator](https://tools.calculators24.com/legal-law/personal-legal/filing-fee-calculator) ### Education & Academics - [Semester GPA Calculator](https://tools.calculators24.com/education-academics/grades-gpa/semester-gpa-calculator) - [Cumulative GPA & Target Semester Forecasting Calculator](https://tools.calculators24.com/education-academics/grades-gpa/cumulative-gpa-calculator) - [High School Weighted GPA & AP/IB Course Rigor Calculator](https://tools.calculators24.com/education-academics/grades-gpa/weighted-gpa-calculator) - [Unweighted GPA Calculator](https://tools.calculators24.com/education-academics/grades-gpa/unweighted-gpa-calculator) - [AP Course Weight Calculator](https://tools.calculators24.com/education-academics/grades-gpa/ap-course-weight-calculator) - [IB Course Weight Calculator](https://tools.calculators24.com/education-academics/grades-gpa/ib-course-weight-calculator) - [Honors Weight Calculator](https://tools.calculators24.com/education-academics/grades-gpa/honors-weight-calculator) - [Dual Enrollment Weight Calculator](https://tools.calculators24.com/education-academics/grades-gpa/dual-enrollment-weight-calculator) ### Environmental & Sustainability - [Personal Carbon Footprint Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/personal-carbon-footprint-calculator) - [Household Carbon Footprint & EPA Equivalency Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/household-carbon-footprint-calculator) - [Corporate GHG Protocol Scope 1, 2 & 3 Emissions Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/business-carbon-footprint-calculator) - [Product Carbon Footprint Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/product-carbon-footprint-calculator) - [Supply Chain Emissions Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/supply-chain-emissions-calculator) - [Scope 1 Emissions Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/scope-1-emissions-calculator) - [Scope 2 Emissions Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/scope-2-emissions-calculator) - [Scope 3 Emissions Calculator](https://tools.calculators24.com/environmental-sustainability/carbon-climate/scope-3-emissions-calculator) ### Agriculture & Farming - [Planting Density Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/planting-density-calculator) - [Seed Rate Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/seed-rate-calculator) - [Seeds per Acre Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/seeds-per-acre-calculator) - [Germination Rate Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/germination-rate-calculator) - [Emergence Rate Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/emergence-rate-calculator) - [Population Stand Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/population-stand-calculator) - [Yield Potential Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/yield-potential-calculator) - [Actual Yield vs Potential Calculator](https://tools.calculators24.com/agriculture-farming/crop-production/actual-yield-vs-potential-calculator) ### Personal Development & Productivity - [Time Value of Money (Personal) Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/time-value-of-money-personal-calculator) - [Hourly Worth Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/hourly-worth-calculator) - [Task ROI Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/task-roi-calculator) - [Priority Score Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/priority-score-calculator) - [Eisenhower Matrix Score Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/eisenhower-matrix-score-calculator) - [Quadrant 2 Time Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/quadrant-2-time-calculator) - [Maker vs Manager Time Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/maker-vs-manager-time-calculator) - [Deep Work Hours Calculator](https://tools.calculators24.com/personal-development-productivity/time-management/deep-work-hours-calculator) ### Astronomy & Space Science - [Kepler's Third Law Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/kepler-s-third-law-calculator) - [Orbital Period Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/orbital-period-calculator) - [Orbital Velocity Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/orbital-velocity-calculator) - [Orbital Radius Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/orbital-radius-calculator) - [Escape Velocity Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/escape-velocity-calculator) - [Gravitational Force Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/gravitational-force-calculator) - [Surface Gravity Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/surface-gravity-calculator) - [Tidal Force Calculator](https://tools.calculators24.com/astronomy-space-science/celestial-mechanics/tidal-force-calculator) ### Retirement Planning - [401(k) Growth Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/401k-growth-calculator) - [Roth 401(k) Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/roth-401k-calculator) - [403(b) Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/403b-calculator) - [457(b) Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/457b-calculator) - [SEP-IRA Contribution & Tax Deduction Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/sep-ira-calculator) - [SIMPLE IRA Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/simple-ira-calculator) - [Traditional IRA Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/traditional-ira-calculator) - [Roth IRA vs. Taxable Brokerage Calculator](https://tools.calculators24.com/retirement-planning/retirement-accounts/roth-ira-calculator) ### Travel & Transportation - [Flight Distance Calculator](https://tools.calculators24.com/travel-transportation/air-travel/flight-distance-calculator) - [Flight Time Calculator](https://tools.calculators24.com/travel-transportation/air-travel/flight-time-calculator) - [Flight Carbon Footprint Calculator](https://tools.calculators24.com/travel-transportation/air-travel/flight-carbon-footprint-calculator) - [Fuel Surcharge Calculator](https://tools.calculators24.com/travel-transportation/air-travel/fuel-surcharge-calculator) - [Baggage Fee Calculator](https://tools.calculators24.com/travel-transportation/air-travel/baggage-fee-calculator) - [Checked Bag Cost Calculator](https://tools.calculators24.com/travel-transportation/air-travel/checked-bag-cost-calculator) - [Oversized Bag Cost Calculator](https://tools.calculators24.com/travel-transportation/air-travel/oversized-bag-cost-calculator) - [Overweight Bag Cost Calculator](https://tools.calculators24.com/travel-transportation/air-travel/overweight-bag-cost-calculator)