Unit conversions
Browse conversion calculators by quantity
400 directed calculators are organized into 20 family hubs, each with a five-unit reference table, named variants and authoritative sources.
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Transparent calculators for practical decisions
Every calculator includes its formula, assumptions, a worked example and practical limits. Your inputs remain in your browser.
Marketing calculators
13 toolsmarketing
ROAS Calculator
Measure how much advertising revenue you generate for every unit of ad spend.
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Break-even ROAS Calculator
Find the minimum ROAS required to cover cost of goods before other operating costs.
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Marketing ROI Calculator
Estimate contribution-based return from incremental revenue, contribution margin and direct marketing cost.
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Advertising Cost of Sales Calculator
Calculate advertising spend as a percentage of attributed sales revenue.
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Customer Acquisition Cost Calculator
Calculate the blended cost of acquiring each new customer.
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Conversion Rate Calculator
Calculate the percentage of visitors or sessions that complete a target action.
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CPM Calculator
Calculate advertising cost for every one thousand impressions.
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CPA Calculator
Calculate the advertising cost required for each acquisition or action.
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Marketing Efficiency Ratio Calculator
Compare total business revenue against total advertising spend.
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Click-Through Rate Calculator
Calculate click-through rate from clicks and impressions without applying a universal benchmark.
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AdSense Revenue Calculator
Model estimated publisher earnings from page views and an assumed page RPM.
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Keyword Golden Ratio Calculator
Calculate the Keyword Golden Ratio from an allintitle result count and an estimated monthly search volume.
Open calculatorE-commerce calculators
3 toolsecommerce
Average Order Value Calculator
Calculate average revenue generated by each completed order.
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E-commerce Profit Calculator
Estimate store profit after product, advertising, platform, payment and shipping costs.
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Selling Price Calculator
Calculate the selling price needed to preserve a target gross margin after entered unit costs.
Open calculatorBusiness metric calculators
11 toolsbusiness metrics
Customer Lifetime Value Calculator
Estimate gross-profit customer lifetime value from purchasing behavior and margin.
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LTV to CAC Ratio Calculator
Compare customer lifetime value with the cost required to acquire that customer.
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Profit Margin Calculator
Calculate profit and profit margin from revenue and total costs.
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Markup Calculator
Calculate markup and unit profit from cost and selling price.
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Contribution Margin Calculator
Measure revenue remaining after variable costs to cover fixed costs and profit.
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Break-even Point Calculator
Calculate the unit sales and revenue required to cover fixed and variable costs.
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Customer Churn Rate Calculator
Calculate the percentage of starting customers lost during a period.
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Customer Retention Rate Calculator
Measure the percentage of starting customers retained after excluding new additions.
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Market Share Calculator
Calculate a company's sales share of a defined market and the sales needed for a target share.
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Employee Turnover Cost Calculator
Total selected recruiting, vacancy-cover and onboarding costs for a number of employee separations.
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Simple Payback Period Calculator
Estimate the years needed for a stated initial cost to be recovered by stated annual savings.
Open calculatorInventory calculators
2 toolsinventory
Inventory Turnover Calculator
Calculate inventory turnover and the implied inventory conversion period from cost of goods sold and average inventory.
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Reorder Point Calculator
Estimate the inventory level that triggers replenishment from daily demand, lead time and safety stock.
Open calculatorProfessional calculators
4 toolsprofessional
Working Hours Calculator
Calculate net working hours from a same-day start time, end time and unpaid break.
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Time Zone Converter
Convert an entered local clock time between two UTC offsets for a stated date and offset scenario.
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Project Timeline Calculator
Estimate a sequential project duration from work, review and contingency days that you choose.
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Freelance Rate Calculator
Calculate a planning hourly rate from an annual revenue target, annual business costs and billable hours.
Open calculatorEducation calculators
6 toolseducation
Reading Time Calculator
Estimate reading time from a word count and a reading rate you choose in words per minute.
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Weighted Grade Calculator
Calculate a current weighted course grade from three percentage scores and their stated course weights.
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Study Planner Calculator
Break a reading workload into daily and session-sized targets using the study days and sessions you choose.
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Question Grade Calculator
Calculate a percentage score from correct answers and the total questions included.
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Pomodoro Calculator
Plan a sequence of focus sessions and short breaks using minutes you choose.
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10 to 15 Grade Calculator
Convert a score on a stated 10-point scale to the proportional value on a 15-point scale without applying a school-specific grading policy.
Open calculatorDate and time calculators
5 toolsdates time
Future Age Calculator
Add a chosen number of years to a current age for a simple future-age planning scenario.
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ISO Week Number Calculator
Find the ISO week number and ISO week-year for an entered Gregorian calendar date.
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Date Difference Calculator
Calculate the whole calendar-day interval between two entered ISO-style dates.
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Working Days Calculator
Count Monday-to-Friday working days, weekend days and calendar days in a stated Gregorian date interval.
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Recurring Dates Calculator
Find the final Gregorian date in a fixed-day recurring schedule from a start date, interval and occurrence count.
Open calculatorEveryday calculators
3 toolseveryday
Fuel Consumption Calculator
Calculate fuel used per 100 kilometres and distance per litre from a measured trip.
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Tip Calculator
Calculate a chosen gratuity amount, the total bill and an optional equal per-person amount.
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Carbon Footprint Calculator
Estimate carbon dioxide equivalent from an activity amount and an emission factor you enter.
Open calculatorHome calculators
9 toolshome
Paint Coverage Calculator
Estimate paint volume from surface area, product coverage, coat count and an explicit waste allowance.
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Room Dimensions Calculator
Calculate floor area, room volume and wall area for a rectangular room from measured dimensions.
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Tile Coverage Calculator
Estimate the number of rectangular tiles needed for a rectangular floor with a stated waste allowance.
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Electricity Cost Calculator
Estimate the energy-charge portion of an electricity bill from kilowatt-hours, an entered rate and billing days.
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Room Lighting Calculator
Estimate a lamp count from a rectangular room, an illuminance target you choose and stated lamp lumens.
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Moving Cost Calculator
Total an entered moving-service quote, packing, travel and contingency costs for a planning scenario.
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Solar Panel Output Calculator
Estimate daily and annual photovoltaic energy from stated system capacity, sun hours and system losses.
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Appliance Energy Use Calculator
Calculate an appliance’s electricity use in watt-hours and kilowatt-hours from its stated power, daily running time and number of days.
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Energy Efficiency Calculator
Calculate the energy efficiency percentage and losses from entered useful energy output and total energy input for one matched scenario.
Open calculatorTravel calculators
2 toolstravel
Baggage Weight Calculator
Add measured packed-item weights and compare the total with an airline baggage limit you enter.
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Trip Fuel Cost Calculator
Estimate fuel volume and fuel cost for a planned trip from distance, vehicle efficiency and an entered fuel price.
Open calculatorGardening calculators
4 toolsgardening
Garden Irrigation Calculator
Estimate irrigation water volume from a rectangular garden area, a chosen water depth, events and system efficiency.
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Compost Mix Calculator
Calculate a two-material compost carbon-to-nitrogen ratio from entered masses and measured or documented composition percentages.
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Fertilizer Amount Calculator
Calculate product quantity from a measured area and the application rate printed on a product label.
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Sunlight Duration Calculator
Calculate local daylight duration from entered sunrise and sunset clock times without estimating location conditions.
Open calculatorPet calculators
1 toolspets
Pet Cost Calculator
Estimate annual pet expenses from recurring monthly costs and annual one-time costs that you enter.
Open calculatorTechnology calculators
4 toolstechnology
Storage Capacity Calculator
Convert decimal gigabytes to bytes and binary gibibytes while showing the unit-system difference.
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Battery Runtime Calculator
Estimate runtime from battery capacity, usable charge share and a steady direct-current load.
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Internet Download Time Calculator
Estimate ideal file-download time from a decimal file size and a measured download speed in Mbps.
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Mobile Data Duration Calculator
Estimate how many days a mobile-data allowance lasts from the allowance and a chosen average daily use.
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