時間・日付 計算機
Calculate date differences, exact age, and time between events. Enter two dates — see days, weeks, months, and years between them. Free.
種類別に見る
Time Calculators
Add and subtract hours, minutes, and seconds for any calculation. Enter time values — see the result in HH:MM:SS and decimal hours. Free.
7個の計算機
Date Calculators
Calculate age, date differences, and calendar tools. Enter your date — see age, days since/until, and day of the week. Free.
6個の計算機
Time Conversions
Convert between time units — seconds, minutes, hours, days, weeks, months, years. Enter any duration — see all equivalent time units. Free.
12個の計算機
Time Calculators
すべて見るHours 計算機
Add and subtract hours and minutes for scheduling. Enter time values — see total duration with decimal hours conversion. Free.
Hours & Minutes 計算機
Perform time arithmetic with hours and minutes. Enter your times — see the total with AM/PM format and decimal conversion. Free.
Time 計算機
Add, subtract, multiply, and divide time values. Enter your hours and minutes — see the result with decimal conversion. Free.
Work Hours 計算機
Calculate total work hours for any period. Enter start and end times with breaks — see regular hours, overtime, and weekly totals. Free.
カウントダウンタイマー
Count down to any future date or event. Enter the target date — see days, hours, minutes, and seconds remaining. Free.
ストップウォッチ
Use a digital stopwatch with lap tracking. Enter laps — see split times, total time, and fastest/slowest lap comparison. Free.
Date Calculators
すべて見るAge 計算機
正確な年齢を年・月・日・時間・分で計算します。生年月日を入力すると、正確な年齢と次の誕生日を表示します。
Date Difference 計算機
Calculate the exact number of days, weeks, and months between two dates. Enter start and end date — see all units with weekday count. Free.
Date 計算機
Add or subtract days, weeks, or months from any date. Enter a date and duration — see the resulting date with day of week. Free.
日数と営業日
Count days between dates with business days option. Enter start and end dates — see total days, business days, and weekends. Free.
曜日
Find the day of the week for any date in history or the future. Enter the date — see day name, day number, week number, and calendar facts. Free.
私は何歳？
Calculate your exact age in years, months, days, hours, and minutes. Enter date of birth — see precise age with next birthday countdown. Free.
Time Conversions
すべて見るTime to 小数
Convert time in hours and minutes to decimal hours. Enter HH:MM — see decimal hours for timesheet, billing, and payroll calculations. Free.
小数 to Time
Convert decimal hours to hours and minutes. Enter decimal time (e.g. 2.75) — see HH:MM format for timesheets and billing. Free.
Military Time コンバーター
Convert between 12-hour and 24-hour (military) time. Enter either format — see the other with AM/PM and 24h equivalents. Free.
時間から分
Convert hours to total minutes. Fast and accurate result with formula, step-by-step method and unit overview. Free tool.
ISO Week Number 計算機
Find the ISO 8601 week number for any date. Enter your date — see week number, year, and first/last day of that week. Free.
Quarter of Year 計算機
Find which fiscal or calendar quarter any date falls in. Enter your date — see quarter number, Q start/end dates, and days remaining. Free.