Northstar Numbers
Free online calculators and utilities for everyday tasks — fast, simple, and always free.
Tip Calculator
Quickly calculate restaurant tips and optionally split the bill between multiple people.
Use calculator →Days Between Dates Calculator
Find the number of days and duration between two calendar dates.
Use calculator →Percentage Change Calculator
Find the percent increase or percent decrease from one value to another.
Use calculator →Percentage Calculator
Calculate what is X% of Y, what percent X is of Y, or X increased or decreased by Y%.
Use calculator →Time Between Times Calculator
Find the duration between two times in hours and minutes, including overnight ranges.
Use calculator →Salary to Hourly Calculator
Convert annual salary to hourly pay or hourly wages to yearly salary, with pay breakdown by period.
Use calculator →Pay Raise Calculator
See how a raise changes your pay. Enter current pay and a percentage or flat-dollar raise for a clear before/after comparison and period breakdown.
Use calculator →Overtime Pay Calculator
Estimate overtime pay from hourly wage, overtime hours, and multiplier (e.g. 1.5x). See overtime rate, total overtime pay, and optional total pay with regular hours.
Use calculator →Age Calculator
Calculate age from a date of birth with an optional reference date and a detailed breakdown of elapsed time.
Use calculator →Date Add and Subtract Calculator
Add or subtract days from a given date to quickly find the resulting calendar date.
Use calculator →Business Days Calculator
Calculate the number of business days between two dates, excluding weekends by default.
Use calculator →Unit Converter
Convert between common measurements including length, weight, temperature, and volume.
Use calculator →Countdown Calculator
See how much time is left until a future date with a clear days, hours, and minutes breakdown.
Use calculator →Ratio Calculator
Simplify ratios to lowest terms and solve for a missing value in equivalent ratios.
Use calculator →Average Calculator
Calculate the mean of a list of numbers. Enter values separated by commas or newlines for an instant average, count, and sum.
Use calculator →Fraction Decimal Converter
Convert between fractions and decimals in either direction. Enter a fraction (numerator and denominator) or a decimal for instant results and percentage.
Use calculator →Loan Payment Calculator
Estimate your monthly payment from loan amount, interest rate, and term. See total paid and total interest in a clear breakdown.
Use calculator →Compound Interest Calculator
Calculate future value with compound interest. Enter initial amount, rate, time, and compounding frequency. Optional monthly contributions and a clear growth breakdown.
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