Unit Converter & Calculator Hub

Calculate monthly payments, total interest, and view amortization schedule.

Calculate tip amount and split the bill between multiple people.

Calculate your Body Mass Index and see your weight category.

Calculate percentages, percentage change, and more.

Add, subtract, multiply, and divide fractions with step-by-step working shown.

Calculate the exact difference between two dates.

Calculate your exact age in years, months, and days, and find out how many days until your next birthday.

Calculate how your investment grows over time with compound interest and optional regular contributions.

Calculate monthly payments, total interest, and total cost on personal loans.

Calculate sales tax amount and total price for any US state or custom rate.

Calculate discount amounts and final prices with percentage or dollar-off discounts.

Baking and cooking substitution calculator. Find ingredient swaps with automatic quantity scaling.

Convert between annual, monthly, biweekly, weekly, and hourly pay rates.

Calorie and TDEE calculator. Find your Total Daily Energy Expenditure and BMR with Mifflin-St Jeor and Harris-Benedict equations, plus macronutrient breakdown for your caloric goals.

Estimate the cost of running appliances based on wattage, usage hours, and electricity rate.

Calculate running pace, time, or distance. Enter any two values to find the third, with split times for your run.

Pregnancy and due date calculator. Estimate your due date from last menstrual period or conception date, with week-by-week pregnancy timeline.

Calculate the area of rooms and spaces from dimensions. Supports multiple shapes and multi-room totals.

Calculate voltage, current, resistance, or power from any two known values using Ohm's Law and power formulas.

Calculate electrical power. Convert watts to amps, amps to watts, and volts to watts for DC, single-phase, and three-phase AC circuits.

Find the minimum wire gauge (AWG) for a given load based on NEC 310.16 ampacity tables and voltage drop limits.

Calculate voltage drop over a wire run for single-phase or three-phase circuits, based on wire gauge, distance, and current.

Decode resistor values from 4, 5, or 6 color bands, or find the color code for any resistance value and tolerance.

Solve for output voltage or either resistor in a two-resistor divider, with optional load to show the real-world loading effect.

Calculate the current-limiting resistor for an LED or LED chain from supply voltage, forward voltage, and forward current.

Estimate how long a battery lasts from its capacity, the load it drives, efficiency, and an optional Peukert correction.

Calculate frequency, period, duty cycle, and pulse width for the 555 timer IC in astable (oscillator) or monostable (one-shot) mode.

Combine up to 10 resistors in series or parallel. Live SVG schematic, total resistance, conductance, and optional current and power from an applied voltage.

Design a first-order RC low-pass or high-pass filter. Solve for cutoff frequency, capacitance, or resistance, and read attenuation and phase at any probe frequency.

Calculate AC power factor, phase angle, apparent power, and reactive power. Size correction capacitors to improve PF for single-phase or three-phase systems.

Combine inductors in series or parallel, and calculate stored energy, inductive reactance, and RL time constant. Live SVG schematic, smart unit formatting.

Combine capacitors in series or parallel, and calculate stored charge Q = CV, energy E = ½CV², and the RC time constant. Live SVG schematic, smart unit formatting.

Calculate Return on Ad Spend (ROAS) from revenue and ad spend, or solve for the missing input. Shows ratio, percentage, and break-even status.

Calculate Cost Per Click (CPC) from total cost and clicks, or solve for the missing input. The IAB standard pricing metric for paid search and performance advertising.

Calculate Cost Per Mille (CPM) from total cost and impressions, or solve for the missing input. The IAB standard pricing metric for impression-based advertising.

Calculate markup percentage, selling price, or cost. Includes margin-to-markup converter and shows gross margin, profit, and price multiplier.

Calculate the break-even point in units, fixed costs, selling price, or variable cost per unit. Shows contribution margin and break-even revenue.

Calculate gross, operating, and net profit margins from revenue and costs. Solve for revenue or COGS at a target margin.