Time & Date Calculators

7 live calculators · free, instant & private

Age calculatorFree, instant and private — runs entirely in your browser.Open calculator →Time calculatorAdd/subtract durations, hours between times, decimal hours for payroll.Open calculator →Date difference calculatorDays between two dates, including a working-days-only count.Open calculator →Countdown CalculatorLive days, hours, minutes and seconds to any date — with working days left and event presets.Open calculator →Business Days CalculatorUS federal and UK bank holidays built in, plus custom weekend patterns.Open calculator →Days between dates calculatorExact gap in days, weeks and business days — or add days to a date.Open calculator →Hours calculatorFree, instant and private — runs entirely in your browser.Open calculator →

Related everyday calculators

From the other everyday sub-categories — same engine, same privacy.

Tip calculatorFree, instant and private — runs entirely in your browser.Food & Dining →Grade calculatorWhere you stand now — and exactly what you need on the final to hit your target.School & Grades →Fuel Cost calculatorFree, instant and private — runs entirely in your browser.Everyday →Grocery Budget calculatorFree, instant and private — runs entirely in your browser.Food & Dining →GPA calculatorWeighted or unweighted, with +/- grades, pass/fail exclusions and a cumulative figure.School & Grades →Roman numerals calculatorConverts both directions and validates subtractive form.Everyday →

Guides for time & date

Worked examples and the reasoning behind these calculators. Browse all guides →

HealthWhat Time Should I Go to Bed?Aug 12, 2026 · 5 min read EverydayHow to Calculate Your Exact Age (Leap Years Included)Aug 8, 2026 · 4 min read EverydayBusiness Days vs Calendar DaysAug 1, 2026 · 5 min read EverydayMinutes to Decimal Hours: The Payroll Conversion ChartJul 29, 2026 · 4 min read Finance$25 an Hour Is How Much a Year?Jul 14, 2026 · 4 min read OtherHow Old Is My Dog in Human Years?Jun 17, 2026 · 6 min read

About these calculators

Date maths is deceptively fiddly: months have different lengths, leap years break naive arithmetic, and "three months from now" has more than one defensible answer. These tools handle those cases explicitly rather than approximating with 30-day months.

The age calculator gives years, months and days plus totals in weeks, days and hours. Date difference and days-between answer the same question two ways — inclusive and exclusive of the end date — because contracts and deadlines disagree on which they mean. The hours calculator adds up shifts with break deductions, and countdowns run live to any moment you choose.

More from ListCalc

Every category, same promise: runs in your browser, shows its math, never sees your numbers.

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