Calculator methods you can inspect

Charging cost = miles x kWh per 100 miles / 100 x electricity price / (1 - charging loss)

Use your actual vehicle efficiency and electricity rate for a useful estimate.

Accessed July 13, 2026

This is an energy-cost estimate, not a charger quote, utility bill, vehicle range prediction, charging-speed forecast, or brand-specific charging recommendation.

Use the actual EV's kWh per 100 miles, the applicable home or public charging price, and a reasonable charging-loss estimate. Weather, driving conditions, fees, idle charges, and time-varying tariffs can change actual cost.

Points grade = total points earned / total points possible x 100; weighted grade = sum(category score x category weight) / total entered weight

Points mode gives higher-point assignments more influence. Weighted mode follows category weights and normalizes a partial set of categories across the weight entered.

Current guide; accessed August 3, 2026

The result is not an official course record, syllabus interpretation, instructor decision, transcript grade, or promise that a learning platform applies the same policies.

Use points mode only when total points determine the grade, or weighted mode when the entered category weights match the syllabus. Dropped work, ungraded items, late penalties, extra credit, curves, caps, and platform settings can change the official result.

Total cost = miles x cost per mile x trip count + fixed charges

Keep the cost-per-mile basis consistent: fuel-only, reimbursement, or all-in operating cost.

Page last reviewed or updated July 28, 2026

This is arithmetic on the selected rate, not an IRS deduction calculation, proof of business use, employer reimbursement rule, tax filing position, or statement of actual driving costs.

Use road miles and the rate that actually applies to the scenario. Eligibility, documentation, purpose, vehicle rules, employer policy, tolls, parking, and actual expenses remain outside this conversion.

APR is the annualized rate that makes the payment stream equal the net amount received after fees

This calculator uses an iterative present-value estimate for fixed monthly payments.

Last reviewed January 30, 2024

This numerical estimate is not a lender's Truth in Lending disclosure, loan offer, legal determination of finance charges, or substitute for the APR in the signed agreement.

The estimate assumes the entered fees are deducted upfront, payments are equal and monthly, and the term is expressed in whole months. Different fee treatment, payment timing, or irregular cash flows can change APR.

Monthly car cost = loan or lease payment + insurance + fuel or charging + maintenance and repairs + registration and taxes + parking and tolls + other vehicle costs

The budget gap compares that total with the monthly car-cost cap you enter. Income left subtracts total car cost from the take-home income you enter.

Last reviewed September 12, 2023

This is not a lender approval, affordability recommendation, credit decision, vehicle quote, insurance quote, or complete household budget.

Enter monthly estimates for the vehicle and your own cap. Housing, food, debt, savings, irregular costs, mileage, insurance, taxes, financing terms, and repairs can materially change what is comfortable.

Total cost = max(advance x fee percentage, minimum fee) + ATM fee + advance x (APR / 365) x days

The estimate applies simple daily interest to the advance amount. Issuer terms may compound differently or treat fees as interest-bearing balances.

Current guidance; accessed August 3, 2026

This is not an issuer statement, payoff quote, contract interpretation, fee disclosure, recommendation to borrow, or reconstruction of the issuer's compounding and payment-allocation method.

The estimate assumes the higher of the entered percentage fee or minimum fee, one entered ATM fee, simple daily interest on the advance amount, and no grace period. Issuer terms, compounding, fee treatment, and payment allocation can change the actual cost.

Weekly fuel cost = round-trip miles x commute days / MPG x gas price; weekly total = fuel cost + parking and tolls

The all-in estimate uses your cost-per-mile input as a broader proxy for vehicle operating cost.

Page last reviewed or updated July 28, 2026

This is a planning estimate, not an IRS deduction calculation, tax determination, employer reimbursement rate, accounting record, or measurement of actual vehicle costs.

Enter the distance, travel pattern, fuel economy, and prices that apply to the scenario. The IRS option is only a visible comparison reference; parking, tolls, route variation, taxes, reimbursements, and actual ownership costs can materially change the result.

Future value = principal x (1 + r)^n + monthly contribution x (((1 + r)^n - 1) / r), where r is monthly return and n is months

This calculator assumes monthly compounding, steady end-of-month contributions, and a constant annual return.

Current calculator; accessed July 13, 2026

This is a constant-return projection, not a forecast, guaranteed return, account statement, security recommendation, or substitute for investment and tax advice.

The result assumes a constant annual return compounded monthly and equal end-of-month contributions. It does not model volatility, taxes, fees, inflation, missed contributions, or changing returns.

Interest = average daily balance x (APR / 365) x days in billing cycle

Actual issuers may calculate balances and grace periods differently, so use statements for official numbers.

Last reviewed January 22, 2024

This is not an issuer statement, payoff quote, grace-period determination, or reconstruction of transactions, fees, multiple APR balances, and the issuer's exact daily-balance method.

The entered balance must represent the cycle's average daily balance and the APR must apply to that balance. The estimate assumes APR divided by 365 and excludes new transactions, fees, grace periods, and multiple rate buckets.

Back-end DTI = total monthly debt payments / gross monthly income x 100

Front-end DTI uses housing payment only. Back-end DTI includes housing plus other recurring monthly debt payments.

Last reviewed August 28, 2023

The ratios are not a lender underwriting decision, approval threshold, credit assessment, affordability recommendation, or substitute for the debts and income definitions a lender applies.

Use gross monthly income and include every recurring monthly debt payment relevant to the comparison. Omissions, variable income, lender adjustments, and different housing-payment definitions can materially change the ratio.

Monthly payment = principal x monthly rate / (1 - (1 + monthly rate)^-months)

Extra payments are applied after the required amortized payment to estimate faster payoff and interest savings.

Last reviewed May 28, 2024

This is not a lender quote, payoff statement, loan agreement, refinancing recommendation, or calculation of variable rates, fees, penalties, or lender-specific payment allocation.

The calculation assumes a fixed annual rate, monthly compounding, equal scheduled payments, and any extra amount applied monthly to principal. Fees, day-count conventions, payment dates, and variable rates are excluded.

Affordable payment = min(gross monthly income x housing limit, gross monthly income x total debt limit - monthly debts); affordable price = loan amount from the remaining principal-and-interest budget + down payment

The calculator subtracts estimated monthly property taxes, homeowners or mortgage insurance, and HOA dues before estimating a loan amount from the remaining principal-and-interest budget.

Current guide; accessed July 13, 2026

This is not mortgage preapproval, lender underwriting, a property valuation, an interest-rate quote, or a recommendation that the maximum estimated price is affordable for the household.

The estimate assumes the entered gross income, debts, down payment, fixed rate, term, taxes, insurance, HOA, and front-end and back-end limits are complete. PMI, closing costs, maintenance, reserves, and lender adjustments are not automatically added.

Monthly mortgage payment = amortized principal-and-interest payment + property tax / 12 + monthly insurance + monthly HOA

The calculator also estimates total interest from the principal-and-interest payment over the selected loan term.

Current worksheet; accessed July 13, 2026

This is not a lender quote, official loan estimate, approval decision, escrow statement, payoff amount, or complete ownership budget.

The loan uses a fixed annual rate and equal monthly payments. Property tax, insurance, and HOA remain constant; PMI, closing costs, maintenance, utilities, rate changes, and lender-specific escrow adjustments are excluded unless entered elsewhere.

Cost difference = estimated owner net cost - estimated rent cost

Owner net cost equals down payment, closing costs, and ownership payments minus estimated equity after sale. Rent cost sums monthly rent with annual rent growth.

Current guide; accessed July 13, 2026

The comparison is not a recommendation to rent or buy, a forecast of home value or rent, a lender decision, a tax analysis, or personalized financial advice.

The result assumes the entered fixed mortgage rate, stay period, ownership costs, rent growth, appreciation, closing costs, and selling costs. It excludes tax deductions, investment opportunity cost, PMI, major repairs, moving costs, and transaction timing differences.

Gross paycheck = annual gross pay / pay periods; take-home = gross x (1 - tax rate)

This is a rough estimate and does not replace payroll or tax withholding calculations.

Current estimator; accessed July 13, 2026

This is not payroll processing, a withholding calculation, a wage-law determination, a pay stub, or a substitute for employer payroll records and the IRS estimator.

The estimate assumes 52 identical workweeks, overtime paid at 1.5 times the entered hourly rate, and one effective tax rate applied to gross pay. It excludes benefit deductions, payroll-tax details, state and local rules, exemptions, bonuses, and irregular schedules.

Estimated tax = max(0, (income - deductions) x tax rate - credits)

This is a simplified planning estimate based on the tax rate you enter, not a full tax filing calculation.

Tax year 2026; accessed July 13, 2026

This is not a tax return, filing calculation, withholding instruction, bracket calculator, eligibility determination, or substitute for current tax forms and qualified tax advice.

The estimate subtracts entered deductions, applies one flat rate to the remainder, subtracts entered credits, and compares entered withholding. It does not model progressive brackets, filing status, payroll taxes, state or local tax, credit phaseouts, alternative taxes, or tax-year changes.

BMI = kg / meters^2; US equivalent = pounds / inches^2 x 703

BMI is a screening measure and does not directly measure body fat or health. The calculator supports US and metric inputs.

June 26, 2024

BMI is a screening estimate, not a diagnosis, body-fat measurement, treatment recommendation, or substitute for professional medical advice.

Use adult inputs, measured height and weight, and the displayed unit conversion. Children, pregnancy, athletes, and individual medical context need different interpretation.

BMR = 10 x weight kg + 6.25 x height cm - 5 x age + 5 for men or -161 for women

BMR is an estimate of resting energy needs before activity is added.

February 1990

This is predicted resting energy expenditure, not indirect calorimetry, maintenance calories, medical nutrition therapy, or a personalized intake target.

Use adult measurements and the coefficient that matches the equation input. Illness, pregnancy, medications, body-composition extremes, and individual metabolism can materially change actual needs.

Men: 86.010 x log10(waist - neck) - 70.041 x log10(height) + 36.76; women: 163.205 x log10(waist + hip - neck) - 97.684 x log10(height) - 78.387

The equation uses inches internally. Metric inputs are converted to inches before calculation, and tape estimates remain sensitive to measurement technique.

June 28, 2013

This is a circumference-based estimate, not a clinical body-composition measurement, diagnosis, service-eligibility decision, or substitute for professional assessment.

Use consistent anatomical landmarks, posture, breathing, and tape tension. Implausible or nonpositive circumference differences are invalid; the displayed estimate is bounded to 2% through 75% for interface safety.

Maintenance calories = Mifflin-St Jeor BMR x activity multiplier

This is a planning estimate. Actual needs vary by body composition, health, and activity.

February 1990

This is a planning estimate, not measured energy expenditure, medical nutrition therapy, or a personalized weight-change prescription.

The estimate assumes the entered measurements are accurate and the chosen activity level reasonably represents the usual routine. Individual needs can differ materially.

Estimated conception date = estimated due date - 266 days

This is an estimate. Conception timing can vary, and clinical dating may use ultrasound or other information.

May 2017; reaffirmed 2025

The result is calendar back-calculation, not proof of conception, ovulation, intercourse, parentage, clinical gestational dating, or a fertile-window determination.

The entered due date must already be a reliable obstetric estimate. Ultrasound, assisted reproduction, irregular cycles, and clinician-assigned dating take precedence over this 266-day subtraction.

Due date = first day of last period + 280 days + cycle adjustment

This is a common estimate and does not replace ultrasound dating or medical care.

May 2017; reaffirmed 2025

This is an LMP-based planning estimate, not clinical dating, prenatal care, an ultrasound interpretation, or a replacement for a clinician-assigned due date.

The estimate assumes the last menstrual period is known and uses the entered cycle adjustment. Assisted reproduction, irregular cycles, and ultrasound findings require clinical dating.

Devine, Robinson, and Miller: base kg + kg per inch x (height in inches - 60); Hamwi: base lb + lb per inch x (height in inches - 60)

The calculator shows four published adult equations side by side and separately derives a BMI 18.5 to 24.9 range. Neither is an individualized target or diagnosis.

2016

The displayed formula spread and BMI range are educational references, not a personal target, diagnosis, treatment plan, or substitute for clinical judgment.

Use for adults with an accurate height and a selected historical female or male formula reference. Children and teens, pregnancy, major muscle or fluid changes, medical conditions, medication dosing, nutrition prescriptions, and treatment decisions need an appropriate protocol and qualified clinical guidance.

Protein grams = protein calories / 4; carb grams = carb calories / 4; fat grams = fat calories / 9

Protein and carbohydrates use about 4 calories per gram. Fat uses about 9 calories per gram.

January 2020

The arithmetic does not recommend a calorie target or macro ratio and is not medical nutrition therapy, a disease-specific diet, or an assessment of food quality.

The calorie input and percentages must reflect the user's chosen plan, and the percentages should total 100%. The general energy factors do not model every nutrient-label exception.

Gestational age = days since first day of last menstrual period / 7

A 40-week estimate is commonly counted from the first day of the last menstrual period.

May 2017; reaffirmed 2025

This is an LMP-based planning estimate, not clinical gestational dating, prenatal care, or a replacement for ultrasound and clinician review.

The estimate assumes the last menstrual period and as-of date are correct. Assisted reproduction, irregular cycles, and ultrasound findings require clinical interpretation.

Protein grams per day = body weight in kg x grams per kg target

The adult RDA baseline is 0.8 g/kg for healthy adults; active targets are planning estimates.

March 2016

The selected grams-per-kilogram value is a planning scenario, not a personalized requirement, supplement recommendation, treatment plan, or assessment of protein quality.

Use measured adult body weight and choose a scenario that fits the actual activity context. Pregnancy, kidney disease, illness, energy restriction, elite training, and other clinical needs require qualified guidance.

TDEE = Mifflin-St Jeor BMR x activity multiplier

Activity multipliers are planning estimates, so real-world tracking is still important.

February 1990

This is not measured total energy expenditure, medical nutrition therapy, or a personalized loss or gain prescription; the plus-or-minus 300 calorie scenarios are planning examples.

Use accurate adult measurements and an activity level that represents the usual week. Pregnancy, illness, medications, eating-disorder recovery, body-composition extremes, and changing activity require different guidance.

Estimated total water = reference adequate intake + exercise add-on + hot-weather add-on

Reference adequate intakes include water from both food and beverages.

2005

This is not a hydration prescription, fluid-balance assessment, heat-safety plan, or substitute for thirst, symptoms, medical restrictions, and qualified guidance.

The baseline represents total water from food and beverages for generally healthy people. Climate, exertion, pregnancy, lactation, medications, kidney or heart conditions, and acute illness can change needs substantially.

Bill rate = pay rate x (1 + markup); loaded labor cost = pay rate x (1 + burden); gross margin = (bill rate - loaded labor cost) / bill rate x 100

This calculator defines markup as a percentage of pay rate. If a contract applies markup to loaded cost instead, translate that pricing rule before using the result.

Current methodology; accessed August 3, 2026

This is not a client quote, payroll calculation, employment-law determination, overtime calculation, tax filing, wage recommendation, or statement of net agency profit.

Markup is applied to pay rate, burden must include the costs relevant to the scenario, and all hours use one straight-time rate. Overtime, contract-specific billing, leave, recruiting expense, financing, overhead, and jurisdictional rules require separate treatment.

Term coverage = matched selected terms / all selected terms x 100

Each selected term counts once. Repeating a term does not increase coverage, and the percentage is not an ATS score or hiring prediction.

February 2026

This is not an ATS score, parser simulation, qualification decision, screening prediction, interview prediction, or instruction to add experience the applicant does not have.

Paste accurate redacted plain text, review every suggested term, and include only phrases relevant to the target role. A match means the selected visible term occurs in the resume text; it does not demonstrate context, proficiency, eligibility, document parsing, or hiring outcome.

Remaining characters = character limit - caption characters

The default is an editable 2,200-character planning threshold, not a verified current TikTok maximum. Confirm the current limit in the app before publishing.

User-confirmed TikTok in-app limit

Confirm at time of use

The default 2,200-character value is a Toolkit Shelf planning threshold, not a verified current TikTok maximum, publishing guarantee, display-preview guarantee, or platform policy statement.

The count includes every character in the entered caption. Confirm the current TikTok limit and relevant app surface, then edit the threshold before relying on the remaining-character result.

Page signal report = guarded HTML fetch + redirect follow + title + canonical + meta robots + googlebot + X-Robots-Tag + og:url checks

The checker fetches one public HTML URL, follows up to 5 redirects, and blocks local, private, reserved, credentialed, and non-http destinations before each request.

User-provided public URL

At each run

The report is a bounded static-HTML check, not a Google indexing verdict, rendered-DOM test, authenticated crawl, or substitute for Search Console URL Inspection.

The URL must be publicly reachable over HTTP or HTTPS. Results cover the fetched response, headers, and static HTML within redirect, timeout, and body-size limits.

Heading report = guarded HTML fetch + redirect follow + h1-h6 extraction + outline order + H1, duplicate, empty, and skipped-level checks

The checker fetches one public HTML URL, follows up to 5 redirects, and blocks local, private, reserved, credentialed, and non-http destinations before each request.

User-provided public URL

At each run

The report checks heading markup in one fetched HTML response; it is not a rendered accessibility audit, content-quality verdict, or full-site crawl.

The public response must contain the relevant headings in static HTML. Client-rendered, authenticated, blocked, or truncated content may be absent.

Header report = guarded request + redirect follow + final response status + selected cache, content, indexing, and policy headers

The checker fetches one public URL, follows up to 5 redirects, and blocks local, private, reserved, credentialed, and non-http destinations before each request.

User-provided public URL

At each run

The report describes one observed response and does not prove every region, edge cache, browser, request method, or authenticated state behaves the same way.

The URL must be publicly reachable over HTTP or HTTPS. Header values reflect the server response observed by the checker at that moment.

Image report = guarded HTML fetch + redirect follow + img tag extraction + alt, duplicate, decorative, dimension, srcset, loading, and decoding checks

The checker fetches one public HTML URL, follows up to 5 redirects, and blocks local, private, reserved, credentialed, and non-http destinations before each request.

User-provided public URL

At each run

The report inventories image markup in one response; it cannot decide whether alt text is contextually useful or replace an accessibility review with assistive technology.

Images and alt attributes must exist in the fetched static HTML. Client-rendered, lazy-injected, authenticated, blocked, or truncated content may be absent.

Structured data report = guarded HTML fetch + redirect follow + application/ld+json extraction + JSON parse + @type and @graph summary

The checker fetches one public HTML URL, follows up to 5 redirects, and blocks local, private, reserved, credentialed, and non-http destinations before each request.

User-provided public URL

At each run

The report parses JSON-LD syntax and visible types; it is not Google Rich Results eligibility, schema-policy approval, or a rendered-DOM validator.

JSON-LD must exist in the fetched static HTML and be valid JSON. Client-injected, authenticated, blocked, or truncated markup may be absent.

Share preview report = guarded HTML fetch + redirect follow + title + meta description + Open Graph tags + Twitter Card tags + preview image checks

The checker fetches one public HTML URL, follows up to 5 redirects, and blocks local, private, reserved, credentialed, and non-http destinations before each request.

User-provided public URL

At each run

The report reads static Open Graph and card metadata; it cannot reproduce every platform cache, crop, scraper user agent, or JavaScript-rendered preview.

Preview tags must exist in the fetched static HTML. Platform caches, client rendering, authentication, blocking, and truncation can change real previews.

Link report = guarded HTML fetch + redirect follow + anchor tag extraction + href classification + anchor text and rel attribute checks

The checker fetches one public HTML URL, follows up to 5 redirects, and blocks local, private, reserved, credentialed, and non-http destinations before each request.

User-provided public URL

At each run

The report inventories one page response and does not replace a rendered interaction test, full crawl, link-status audit, or editorial review of anchor meaning.

Links must appear in the fetched static HTML. Client-rendered, authenticated, blocked, or truncated links may be absent from the result.

Redirect report = guarded HEAD request + manual Location following + final status + hop timing + unsafe-destination blocks

The checker blocks localhost, private IPs, reserved IPs, credentialed URLs, and non-http destinations before each request and after each redirect.

User-provided public URL

At each run

The report shows one server-side redirect path, not every browser, geography, user agent, cookie state, cache layer, or authenticated flow.

The URL must be publicly reachable over HTTP or HTTPS. The checker blocks private destinations and follows at most five redirects with bounded timeouts.

Discovery report = guarded origin check + /robots.txt fetch + /sitemap.xml fetch + Sitemap declarations + User-agent * Disallow summary + sitemap loc count

The checker only fetches conventional robots.txt and sitemap.xml URLs for one public origin. It does not crawl the site or simulate a search engine bot.

User-provided public URL

At each run

The report checks conventional root files and basic directives; it is not a search-engine crawl verdict, complete robots parser, sitemap submission, or index-coverage report.

The origin, /robots.txt, and /sitemap.xml must be publicly reachable. Results are bounded by redirect, timeout, and response-size limits.

Password = Web Crypto random selections from the enabled character sets, including at least one character from every enabled set

Selection uses rejection sampling to avoid modulo bias. The displayed entropy is an approximate search-space estimate and is not a security guarantee.

Accessed July 13, 2026

The generator supplies random text, not account protection, secure storage, breach monitoring, phishing resistance, recovery, multi-factor authentication, or a guarantee that a destination accepts the selected characters.

Use a browser with crypto.getRandomValues, select at least one character set, confirm the destination's password rules, keep the result unique, and store it securely. The entropy number is an approximate alphabet-size model rather than a security guarantee.