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From mortgage payments and BMI to binary math and DeFi analysis — JustCalculators.app is your free, instant, all-in-one calculation resource.

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💰 Financial Calculators

401(k) Calculator

Project 401k balance with employer match and tax-deferred growth

Absence Percentage Calculator

Calculate employee absence rate as a percentage of total scheduled work days

Accumulated Depreciation Calculator

Track total depreciation recorded on an asset over its useful life

Additional Funds Needed Calculator

Calculate external financing required to support projected sales growth

After-Tax Cost of Debt Calculator

Calculate the true cost of debt after the tax deduction on interest payments

Calculate Adjusted Gross Income by subtracting above-the-line deductions from gross income

Altman Z-Score Calculator

Predict corporate bankruptcy risk using the Altman five-factor financial health formula

Amortization Calculator

Complete payment-by-payment loan amortization schedule

Annual Income Calculator

Calculate total annual income from hourly, weekly, or monthly earnings

Annuity Calculator

Future value of regular deposits with compound growth

Convert APR to Annual Percentage Yield accounting for compounding frequency

Attrition Rate Calculator

Calculate the percentage of employees or customers lost over a given period

Auto Loan + Amortization

Car loan with complete month-by-month payment schedule

Auto Loan Calculator

Car payments with trade-in value and sales tax

Average Collection Period Calculator

Measure how many days on average it takes to collect accounts receivable

Average Fixed Cost Calculator

Calculate fixed cost per unit of output at any given production level

Beta Stock Calculator

Calculate a stock beta coefficient to measure volatility relative to the market

Bond Equivalent Yield Calculator

Convert discount yield on Treasury bills to an annualized bond equivalent yield

Bounce Rate Calculator

Calculate website bounce rate as a percentage of single-page sessions

Break-Even Calculator

Calculate break-even point in units and revenue from fixed costs, variable costs, and price

Build vs Buy Calculator

Compare total cost of building software in-house versus purchasing a solution

Burn Rate Calculator

Calculate monthly cash burn rate and runway from starting balance and expenses

Business Loan Calculator

Commercial loan payments and cash flow impact

Calculate Customer Acquisition Cost from total sales and marketing spend

CAGR Calculator

Calculate Compound Annual Growth Rate between any two values over a time period

Cap Rate Calculator

Calculate real estate capitalization rate from net operating income and property value

CAPM Calculator

Calculate expected return of an asset using the Capital Asset Pricing Model

Cash Flow Calculator

Calculate net cash flow from operating, investing, and financing activities

Cash-on-Cash Return Calculator

Calculate annual pre-tax cash flow return on actual cash invested in a property

Certificate of deposit value and interest at maturity

Churn Rate Calculator

Calculate monthly or annual customer churn rate and implied average customer lifetime

Closing Cost Calculator

Estimate home buying closing costs including lender fees, title, and prepaid items

Compound Interest Calculator

Investment growth with regular contributions

Consulting Fees Calculator

Calculate hourly consulting rate from desired annual income, overhead, and billable hours

Contribution Margin Calculator

Calculate contribution margin per unit and ratio to cover fixed costs and generate profit

Conversion Rate Calculator

Calculate conversion rate percentage from visitors and conversions for any funnel stage

Cost of Doing Business Calculator

Calculate your true hourly cost of running a business including all overhead and expenses

Cost of Equity Calculator

Calculate the return required by equity investors using CAPM or dividend growth model

Cost of Living Calculator

Compare cost of living between cities using salary, housing, and expense adjustments

Coupon Payment Calculator

Calculate periodic coupon payments on bonds from face value, coupon rate, and frequency

Coupon Rate Calculator

Calculate the coupon rate on a bond from annual interest payments and face value

CPA Calculator (Marketing)

Calculate Cost Per Acquisition from total ad spend and number of conversions

CPC / CPM Calculator

Calculate Cost Per Click or Cost Per Mille from ad spend and impressions or clicks

Credit Card Interest Calculator

True cost of carrying a monthly credit card balance

Credit Card Payoff Calculator

How long and how much to pay off your balance

Calculate Click-Through Rate from impressions and clicks for ads or email campaigns

Customer Lifetime Value Calculator

Calculate CLV from average purchase value, purchase frequency, and customer lifespan

Customer Retention Rate Calculator

Calculate the percentage of customers retained over a given period

Debt Consolidation Calculator

Compare consolidating debts vs. paying separately

Debt-to-Asset Ratio Calculator

Calculate the proportion of assets financed by debt as a measure of financial leverage

Debt-to-Capital Ratio Calculator

Measure financial leverage by comparing total debt to total capital employed

Debt-to-Equity Calculator

Calculate the ratio of total liabilities to shareholders equity for leverage analysis

Debt-to-Income (DTI) Ratio

DTI ratio for mortgage and loan qualification

Depreciation Calculator

Straight-line and declining balance depreciation

Direct Material Price Variance

Calculate the variance between actual and standard cost of direct materials used

Dividend Calculator

Calculate dividend income from shares owned, dividend per share, and payment frequency

Dividend Discount Model Calculator

Value a stock based on the present value of expected future dividend payments

Dividend Payout Ratio Calculator

Calculate the percentage of net income distributed to shareholders as dividends

Dividend Yield Calculator

Calculate annual dividend yield as a percentage of current stock price

Dollar-Cost Averaging Calculator

Calculate investment growth from regular fixed-amount purchases over time

DSCR Calculator

Calculate Debt Service Coverage Ratio to measure ability to cover loan payments from income

Calculate Effective Annual Rate from nominal interest rate and compounding periods

EBITDA Multiple Calculator

Calculate enterprise value as a multiple of EBITDA for company valuation

Effective Corporate Tax Rate

Calculate a corporation effective tax rate from taxes paid and pre-tax income

Effective Tax Rate Calculator

Calculate your effective income tax rate as a percentage of total taxable income

Emergency Fund Calculator

Calculate how much to save in your emergency fund based on monthly expenses and timeline

Enterprise Value Calculator

Calculate total enterprise value from market cap, debt, cash, and minority interests

Calculate Earnings Per Share from net income, preferred dividends, and shares outstanding

Estate Tax Calculator

Federal estate tax based on 2024 exemptions

EV/Sales Ratio Calculator

Calculate the Enterprise Value to Sales ratio for company valuation comparison

Exit Rate Calculator

Calculate the percentage of visitors who leave your site from a specific page

Expense Ratio Calculator

Calculate annual fund expense ratio cost on your investment balance over time

FICA Tax Calculator

Calculate Social Security and Medicare FICA taxes for employees and self-employed

FIFO Calculator

Calculate inventory value and COGS using First In, First Out accounting method

Finance (TVM) Calculator

Solve any time-value-of-money variable

Calculate Full-Time Equivalent employees from part-time and full-time headcount

Google AdSense Calculator

Estimate monthly AdSense revenue from page views, CTR, and cost per click

Graham Number Calculator

Calculate Benjamin Graham intrinsic value estimate from EPS and book value per share

Gross Profit Calculator

Calculate gross profit and gross margin percentage from revenue and cost of goods sold

Gross Rent Multiplier Calculator

Calculate GRM from property price and annual gross rental income for quick valuation

Gross to Net Calculator

Convert gross salary to net take-home pay after taxes and deductions

Holding Period Return Calculator

Calculate total return on an investment over any holding period including income

Hourly to Salary Calculator

Convert an hourly wage to annual, monthly, or weekly salary equivalents

Health Savings Account growth and triple tax advantage

Income Tax Calculator

Estimate federal tax, effective rate, and marginal bracket

Inflation Calculator

How inflation erodes purchasing power over time

Interest Calculator

Simple and compound interest for any loan or savings

Interest Coverage Ratio Calculator

Calculate how easily a company can pay interest expense from operating earnings

Interest Rate Calculator

Find the implied interest rate from loan variables

Intrinsic Value Calculator

Estimate a stock intrinsic value using discounted cash flow analysis

Investment Calculator

Project portfolio growth with contributions and returns

Calculate Internal Rate of Return from an initial investment and future cash flows

Labor Cost Calculator

Calculate total labor cost including wages, benefits, payroll taxes, and overhead

Lease Calculator

Monthly lease payments for cars and equipment

Loan Calculator

Monthly payment and total interest for any installment loan

Lottery Tax Calculator

Calculate federal and state taxes on lottery winnings for lump sum and annuity options

MAGI Calculator

Calculate Modified Adjusted Gross Income for IRA eligibility and ACA subsidy purposes

Margin Calculator

Profit margin and markup for pricing and analysis

Margin of Safety Calculator

Calculate the margin of safety percentage between intrinsic value and market price

Market Cap Calculator

Calculate total market capitalization from current share price and shares outstanding

Markup Calculator

Calculate markup percentage and selling price from cost and desired profit margin

Mileage Reimbursement Calculator

Calculate IRS mileage reimbursement from business miles driven and current rate

Mortgage Calculator

Monthly PITI with amortization, PMI, taxes & insurance

Mortgage Payoff Calculator

See how extra monthly payments reduce payoff time and total interest on your mortgage

Net to Gross Calculator

Calculate gross salary needed to achieve a target net take-home pay after taxes

Net Worth Calculator

Calculate your personal net worth from total assets minus total liabilities

Calculate Net Present Value of future cash flows discounted at your required rate of return

Opportunity Cost Calculator

Calculate the opportunity cost of choosing one investment or decision over another

Overtime Calculator

Calculate overtime pay at 1.5x or 2x rate from regular hourly wage and hours worked

P/E Ratio Calculator

Calculate Price-to-Earnings ratio from stock price and earnings per share

Pay Raise Calculator

Calculate new salary and dollar increase from a percentage pay raise

Paycheck Calculator

Estimate take-home pay after taxes and deductions

Perpetuity Calculator

Calculate the present value of a perpetuity from periodic payment and discount rate

Personal Loan Calculator

Monthly payment for any unsecured personal loan

Estimate monthly Private Mortgage Insurance cost based on loan-to-value ratio

Portfolio Return Calculator

Calculate weighted average portfolio return from individual holdings and their weights

Present Value Calculator

Discounted cash flow and time value of money

Price-to-Book Ratio Calculator

Calculate P/B ratio from current stock price and book value per share

Price-to-Cash Flow Calculator

Calculate P/CF ratio to compare stock price relative to operating cash flow per share

Price-to-Sales Ratio Calculator

Calculate P/S ratio from market capitalization and total annual revenue

Profit Calculator

Calculate gross profit, net profit, and profit margin from revenue and cost inputs

Prorated Salary Calculator

Calculate prorated pay for partial pay periods, new hires, or mid-period terminations

Real Rate of Return Calculator

Calculate inflation-adjusted real return from nominal return and inflation rate

Rental Property Calculator

Cash flow, cap rate, NOI, and real estate ROI

Retirement Calculator

Are you on track? Find your retirement savings gap

Retirement Planner

Comprehensive retirement income gap analysis

Return on Assets Calculator

Calculate ROA from net income and total assets to measure asset efficiency

Return on Equity Calculator

Calculate ROE from net income and shareholders equity using the DuPont formula

Return on Sales Calculator

Calculate operating profit margin as a percentage of net sales revenue

Revenue Calculator

Calculate total revenue, revenue per unit, and growth rate from sales volume and pricing

Revenue Per Employee Calculator

Calculate revenue per employee as a measure of workforce productivity

ROAS Calculator

Calculate Return on Ad Spend from ad revenue generated and advertising cost

ROCE Calculator

Calculate Return on Capital Employed from EBIT and capital employed

Return on investment for any business or investment

ROIC Calculator

Calculate Return on Invested Capital from net operating profit and invested capital

Salary Calculator

Calculate equivalent salary across hourly, weekly, monthly, and annual pay periods

Salary Inflation Calculator

Calculate what salary you need today to maintain purchasing power from a past salary

Salary to Hourly Calculator

Convert annual salary to hourly rate accounting for paid time off and hours per week

Sales Commission Calculator

Calculate total commission earned from sales amount, commission rate, and tiers

Sales Tax Calculator

Calculate tax amount and total price for any rate

Savings Calculator

Project savings balance with deposits and interest

Self-Employment Tax Calculator

Calculate self-employment tax and deductible portion for Schedule SE filing

Sell-Through Rate Calculator

Measure what percentage of inventory sold in a period — track retail efficiency

Sharpe Ratio Calculator

Calculate risk-adjusted return of a portfolio relative to a risk-free benchmark

Simple Interest Calculator

Quick I=PRT interest calculations

Sinking Fund Calculator

Calculate equal periodic deposits needed to reach a future savings target

Sortino Ratio Calculator

Calculate downside risk-adjusted return using only negative volatility in the denominator

State Tax Calculator

Estimate state income tax liability from taxable income and state-specific rates

Stock Average Calculator

Calculate average cost per share when buying the same stock at different prices

Stock Profit Calculator

Calculate profit or loss on a stock trade from buy price, sell price, and shares

Stock Split Calculator

Calculate new share count and price after a stock split or reverse split

Student Loan Calculator

Payments and payoff timeline for federal/private loans

Sustainable Growth Rate Calculator

Calculate the maximum growth rate a company can sustain without external equity financing

Tax Bracket Calculator

See which federal tax bracket your income falls into and effective vs marginal rate

Tax-Equivalent Yield Calculator

Compare taxable and tax-exempt bond yields to find the true after-tax equivalent return

Time and a Half Calculator

Calculate time-and-a-half pay from regular hourly rate for overtime compensation

Times Interest Earned Calculator

Calculate TIE ratio to measure how well earnings cover interest expense obligations

Treynor Ratio Calculator

Calculate market risk-adjusted return using portfolio beta instead of standard deviation

Turnover Rate Calculator

Calculate employee turnover rate as a percentage of average headcount over a period

Value at Risk Calculator

Estimate maximum potential portfolio loss at a given confidence level over a time horizon

Add or remove Value Added Tax for any rate

WACC Calculator

Calculate Weighted Average Cost of Capital from equity, debt, and tax rate inputs

Wage / Salary Calculator

Convert hourly, weekly, monthly, and annual pay rates

Working Capital Calculator

Calculate net working capital from current assets minus current liabilities

❤️ Health & Fitness Calculators

BAC / Blood Alcohol Calculator

Estimate BAC by drinks, weight, sex, and time elapsed

Body Mass Index — imperial and metric units with health range

Calories burned at complete rest (Mifflin-St Jeor)

Body Fat Calculator

Body fat % using US Navy circumference method

Body Surface Area (BSA)

BSA for clinical and pharmaceutical dosing

Calorie Calculator

Daily calorie needs (Mifflin-St Jeor equation)

Conception Calculator

Estimate your conception date from due date or LMP

Due Date Calculator

Estimated due date from LMP or conception date

Ideal Weight Calculator

Four evidence-based IBW formulas compared

Lean Body Mass Calculator

Fat-free mass for accurate nutrition targeting

Macro Calculator

Protein, carbs, and fat targets for your goals

Ovulation Calculator

Fertile window and ovulation day from cycle length

Pace Calculator

Running pace, finish time, or distance from any two values

Pregnancy Weight Gain

IOM-recommended weight gain by pre-pregnancy BMI

Target Heart Rate

Max HR and fat-burn/cardio/threshold training zones

TDEE Calculator

Total daily energy expenditure with activity level

Waist-to-Hip Ratio

Cardiovascular risk from body shape measurements

Water Intake Calculator

Daily hydration needs by weight and activity level

➗ Math Calculators

Algebra Calculator

Solve linear and quadratic equations, simplify expressions

Average Calculator

Mean, weighted average, geometric and harmonic mean

Basic Calculator

Clean four-function calculator with memory, √, % and history

Binary Calculator

Binary arithmetic and conversion between number bases

Circle Calculator

Area, circumference, diameter from any single measurement

Fraction Calculator

Add, subtract, multiply, divide with auto-simplification

Graphing Calculator

Plot functions and visualize equations interactively

Percentage Calculator

X% of Y, what % X is of Y, and % change

Quadratic Formula

Solve ax²+bx+c=0 including complex roots

Rounding Calculator

Round to decimal places or significant figures

Scientific Notation

Convert to/from scientific notation and perform operations

Standard Deviation

Population and sample standard deviation with full analysis

Statistics Calculator

Mean, median, mode, range, variance from any dataset

Triangle Calculator

Area, angles, sides, perimeter from any known values

🔧 Utility Calculators

Exact age in years, months, days plus birthday countdown

Base64 Encoder/Decoder

Encode text to Base64 or decode Base64 strings

Binary to Text Converter

Convert between binary code and readable ASCII text

Engagement Rate Calculator

Social media engagement rate vs. industry benchmarks

Semester and cumulative GPA from letter grades

Password Generator

Strong, secure random passwords with custom settings

Random Number Generator

Random integers in any range

RGB to HEX Converter

Convert color codes for web and CSS design

Sales Tax Calculator

Calculate tax amount and total for any rate

Tip amount, total, and per-person split

TV Viewing Distance

Ideal TV size and viewing distance for your room

Length, weight, volume, temperature, speed and more

₿ Crypto / DeFi Calculators

Crypto Profit Calculator

Calculate profit, loss, and after-tax ROI on any crypto trade — Bitcoin, Ethereum, or any altcoin

Impermanent Loss Calculator

DeFi AMM liquidity pool IL from price changes

🛒 eCommerce Calculators

Amazon Seller Calculator

Referral fee by category, FBA costs, net profit, ROI, and break-even price

Bonanza Fee Calculator

Advertising-tier model: 3.5% organic to 30% maximum exposure

Craigslist Calculator

Free for most items — $5 per vehicle listing by owner

Depop Fee Calculator

10% commission on item price + 2.9%+$0.30 payment processing

eBay Fee Calculator

Final value fees by category, payment processing, and promoted listing costs

Etsy Fee Calculator

6.5% transaction + 3%+$0.25 payment + $0.20 listing fee + optional Etsy Ads

Facebook Marketplace Calculator

Free local pickup — 5% or $0.40 minimum fee for shipped orders

Faire Wholesale Calculator

25% new retailer, 15% reorder, 0% commission via Faire Direct

Grailed Fee Calculator

9% commission + ~3%+$0.30 payment for luxury streetwear and designer resale

Mercari Fee Calculator

10% selling fee + 3% payment processing = 13% total fees

OfferUp Fee Calculator

Free local sales — 12.9% or $1.99 minimum for shipped orders

Poshmark Fee Calculator

$2.95 flat under $15, 20% commission on sales of $15 and over

Reverb Fee Calculator

5% selling fee (max $500) + 3.19%+$0.49 payment for music gear

Ruby Lane Fee Calculator

9.9% service fee + $25/mo maintenance for antiques and collectibles

Shopify Profit Calculator

Transaction fee by plan, Shopify Payments vs third-party gateway, ad spend

StockX Fee Calculator

6–9% by seller level + 3% payment — authentication included in fee

Target Plus Calculator

5–15% referral by category — invite-only marketplace, seller fulfills orders

TikTok Shop Calculator

Platform commission + affiliate creator commission + payment processing

Vinted Calculator

Zero seller fees — buyers pay all platform and payment fees

Walmart Marketplace Calculator

8–15% referral by category — no monthly seller fee

Whatnot Fee Calculator

10% selling + 2.9%+$0.30 payment for live auction and collectibles sales

📬 Shipping

Carrier Comparison Calculator

Compare USPS, UPS, and FedEx side by side — lowest rate highlighted

DHL Shipping Calculator

Express Worldwide and eCommerce rates for domestic and international shipments

DIM Weight Calculator

Calculate dimensional weight for UPS/FedEx (÷139) and USPS (÷166) at once

FedEx Shipping Calculator

Ground, Home Delivery, Express Saver, 2Day, and Overnight with all surcharges

Shipping Profit Calculator

See how shipping charge vs actual cost and packaging affect net profit per order

UPS Shipping Calculator

Ground, 2nd Day Air, Next Day Air with residential and fuel surcharges

USPS Shipping Calculator

Ground Advantage, Priority Mail, Flat Rate, and Media Mail by weight and zone

🏭 3PL Fulfillment

3PL Cost Calculator

Monthly pick fees, storage, receiving, returns, and monthly minimum — total cost per order

3PL vs Amazon FBA Calculator

Side-by-side monthly cost including FBA fees, Q4 storage spikes, and inbound shipping

Red Stag Fulfillment Calculator

$0.46/cu ft storage — specialized for heavy, oversized, fragile, or high-value products

ShipBob Cost Calculator

$40/pallet storage, $35/hr receiving, pick fees by volume tier

ShipMonk Cost Calculator

Cubic foot storage, free receiving, subscription box pricing, and kitting fees

🖨️ Print On Demand

Apliiq Profit Calculator

Premium private-label: woven labels, hang tags, cut-and-sew — no minimum order

Compare All POD Platforms

Every POD platform side by side at your retail price — sorted highest to lowest profit

CustomCat Profit Calculator

Cheapest DTG apparel in POD (~$7.85 tee on PRO) with fast 2–3 day production

Gelato Profit Calculator

Local production in 32 countries — Gelato+ Gold includes free worldwide shipping

Gooten Profit Calculator

Free platform with niche products: candles, area rugs, puzzles, and pillows

Merch by Amazon Calculator

Invite-only, Prime-eligible — royalty = retail minus base cost minus 15% referral fee

Printful Profit Calculator

Base cost, Growth plan discounts up to 33%, extra placements, and marketplace fees

Printify Profit Calculator

Free vs Premium plan — Bella+Canvas from $9.04 on Premium with 20% off

Prodigi Profit Calculator

Giclée fine art prints, canvas, framed art, acrylic prints, and photo books

Redbubble Profit Calculator

Artist marketplace — set your markup above base price, Redbubble handles everything

SPOD Profit Calculator

Free always — 48-hour production guarantee on 99%+ of orders

Spring (Teespring) Calculator

Creator-focused — native YouTube, TikTok Shop, and Twitch merch shelf integration

Teelaunch Profit Calculator

Free — unique catalog including Bluetooth speakers, metal prints, and phone wallets

Zazzle Royalty Calculator

Set royalty rate 5–99% — built-in buyer personalization drives gift and wedding sales

💳 Payment Processing

Payment Gateway Comparison

Compare Stripe (2.9%+$0.30), PayPal (3.49%+$0.49), and Square (2.6%+$0.10) per order

WooCommerce Profit Calculator

Stripe, PayPal, or Square gateway fees + hosting, ad spend, and COGS per order

Why JustCalculators.app?

⚡

Instant Results

All calculations run in your browser — no server delays, no waiting, results appear immediately.

🎯

Accurate Formulas

Every calculator uses clinically- and financially-verified formulas with cited sources.

🔒

Private by Design

Your inputs never leave your device. Zero data collection on what you calculate.

📱

Works on Any Device

Fully responsive — desktop, tablet, and mobile. Any browser, any screen size.

Free Online Calculators for Every Need

JustCalculators.app provides more than 80 free online calculators across five major categories: financial, health & fitness, math, utility, and crypto/DeFi. Every tool delivers instant, accurate results directly in your browser — no registration, no subscription, no downloads required.

Our financial calculators cover the full spectrum of personal and business finance — from calculating a monthly mortgage payment with full amortization to projecting your 401(k) balance at retirement, estimating federal income tax liability, and analyzing the ROI on a rental property investment.

Our health & fitness calculators use scientifically-validated formulas: the Mifflin-St Jeor equation for calorie and TDEE calculations, CDC guidelines for BMI classification, and the US Navy circumference method for body fat estimation.

Whether you're a student solving quadratic equations, a homebuyer comparing 15-year vs. 30-year mortgages, an investor analyzing a rental property's cap rate, or someone tracking their daily nutrition macros — JustCalculators.app has the right tool, available 24/7, completely free.