time and dates
add or subtract two durations in hours, minutes, and seconds. see a signed result when subtraction passes below zero.
enter durations, not clock times. hours may exceed 24; minutes and seconds must each be 00–59.
a duration is an amount of elapsed time, not a time shown on a clock. adding 23:30:00 and 02:00:00 gives 25:30:00, not 01:30:00, because the hours are not wrapped at midnight. this is useful for workloads, video segments, travel legs, and multi-day activities.
the calculator converts both entries to whole seconds, performs the chosen arithmetic, then converts the total back to hours, minutes, and seconds. that approach makes carry and borrowing explicit: 01:59:50 plus 00:00:20 is 02:00:10, while 01:00:00 minus 00:00:01 is 00:59:59.
a negative answer means the second duration exceeded the first. for example, 00:15:00 minus 00:20:00 is -00:05:00. the sign applies to the entire result, not just the hours field. enter positive components and use the operation control for subtraction; a typed negative component is deliberately rejected.
this tool does not calculate the difference between two wall-clock appointments. that problem needs dates, time zones, daylight-saving changes, and a rule for crossing midnight. seconds here are exact arithmetic units, but the accuracy of your source timings remains your responsibility.
| control | what it does | important detail |
|---|---|---|
| first duration | starting amount in hh:mm:ss | hours may be 0–999999; minutes and seconds 00–59. |
| second duration | amount to add or subtract | always enter a nonnegative duration. |
| Operation | chooses addition or subtraction | subtraction computes first minus second. |
| Ergebnis | signed hours, minutes, seconds | hours do not wrap after 24. |
total separate work blocks before converting them to a payroll format.
add clip lengths or subtract a cut from a target runtime.
combine intervals while retaining seconds rather than rounding to minutes.
it does not apply dates, time zones, breaks, or overtime policy. for clock-in and clock-out work, use a work-hours tool and verify payroll rules.
yes. a duration can be longer than a day, and the result never wraps to a 24-hour clock.
with subtraction, the second amount is larger than the first; the minus sign belongs to the whole duration.
each duration is converted to seconds before arithmetic, then decomposed into hours, minutes, and seconds.
no. use 2:15:00 instead; minutes and seconds are limited to 00–59.
no. it handles durations only, not local times or dates.
last reviewed: october 23, 2026. calculations run in your browser. confirm important results independently.
percentage calculator, what percent is, percent of total, calculate percentage, percent finder, quickconver
Berechnen Sie, welchen Prozentsatz eine Zahl von einer anderen Zahl ausmacht, plus den verbleibenden Betrag und das Dezimalverhältnis. Verwenden Sie diesen Prozentrechner für Noten, Rabatte, Fortschritte, Budgets, Umfrageergebnisse, Inventar und alltägliche Vergleiche.
Prozentuale Zunahme-Rechner, Prozentänderungsrechner, Erhöhungsprozentsatz-Formel, prozentuale Steigerung berechnen, Preissteigerungsrechner, quickconver
Berechnen Sie die Erhöhung, prozentuale Steigerung und den Änderungsfaktor zwischen einem ursprünglichen Wert und einem neuen Wert. Verwenden Sie dies für Preise, Einnahmen, Löhne, Verkehrs, Lagerbestände, Messungen und Leistungsbewertungen.
Prozentsatz Abwärtsrechner, Prozentabnahmformel, Verringerungsprozentsatz berechnen, Rabattabwärtsrechner, Prozent verbleibend Rechner, quickconver
Berechnen Sie den Betrag des Rückgangs, den prozentualen Rückgang und den verbleibenden Prozentsatz zwischen einem ursprünglichen Wert und einem neuen Wert. Verwenden Sie dies für Verkaufspreise, Budgetkürzungen, Lagerabbau, Gewichtsänderungen, Nutzungsreduktionen und Leistungsvergleiche.
Bruchrechner, Brüche addieren, Brüche subtrahieren, Brüche multiplizieren, Brüche dividieren, Brüche vereinfachen, quickconver
Berechne die gekürzten Bruchresultate, Dezimalwerte und Prozentsätze für Addition, Subtraktion, Multiplikation und Division. Gib zwei Brüche ein und wähle eine Operation für Hausaufgaben, Rezepte, Messungen, Proportionen oder Alltagmathematik.
Durchschnittsrechner, Mittelwertrechner, Durchschnitt berechnen, Durchschnitt der Zahlen, Summe und Durchschnitt Rechner, Schnellkonvergenz
Berechnen Sie den Durchschnitt, die Summe, die Anzahl, das Minimum und das Maximum einer Liste von Zahlen. Fügen Sie durch Kommas, Leerzeichen, Semikolons oder Zeilen getrennte Werte für Noten, Kosten, Messungen, Ergebnisse und Berichte ein.
watts to amps calculator, watts to amps, convert watts to amps, watt amp calculator, single phase amps calculator, quickconver
calculate estimated single-phase amps from watts, voltage, and power factor. use this watts to amps calculator to compare load-current scenarios while confirming equipment ratings, circuit protection, and applicable electrical rules separately.
amps to watts calculator, amps to watts, convert amps to watts, amp watt calculator, single phase power calculator, quickconver
calculate estimated single-phase watts, kilowatts, and volt-amperes from amps, voltage, and power factor. use this amps to watts calculator to understand a load scenario before relying on nameplate data and qualified electrical design.
kw to amps calculator, kilowatts to amps calculator, kw amp calculator, convert kw to amps, single phase kw to amps, quickconver
calculate estimated single-phase amps from kilowatts, voltage, and power factor. use this kw to amps calculator for transparent power-current scenarios, then confirm the actual installation with equipment data and qualified electrical review.
kva to amps calculator, kva amps calculator, convert kva to amps, kilovolt amps to amps, single phase kva calculator, quickconver
calculate estimated single-phase amps and volt-amperes from kva and voltage. use this kva to amps calculator to compare apparent-power scenarios, then confirm system phase, equipment ratings, and electrical design requirements separately.
amps to kw calculator, amps to kilowatts calculator, amp to kw calculator, convert amps to kw, single phase amps to kw, quickconver
calculate estimated single-phase kilowatts, watts, and apparent power from amps, voltage, and power factor. use this amps to kw calculator for a transparent load estimate before checking nameplate data and qualified electrical design requirements.
voltage drop calculator, voltage drop calculation, wire voltage drop calculator, voltage drop percentage calculator, electrical voltage drop, quickconver
estimate single-phase or three-phase voltage drop from voltage, current, one-way conductor length, and resistance per 1,000 feet. use this voltage drop calculator for planning only and have a qualified electrician verify a real electrical design.
probability calculator, event probability calculator, probability of a or b, independent events, conditional probability, quickconver
calculate both, either, exactly one, neither and conditional probabilities for two events. use independent events or enter a known intersection for dependent events.
time calculator, add time, subtract time, duration calculator, hours minutes seconds calculator, quickconver
add or subtract hours, minutes, and seconds with clear carry handling and signed results. this free time calculator works with durations longer than a day.
sunrise, sunset calculator, sunrise time, sunset time, daylight hours, sun times, quickconver
estimate sunrise, sunset, and daylight for a chosen date, coordinates, and explicit utc offset. handles high-latitude days without a sunrise or sunset.
age calculator, how old am i, years months days, date of birth calculator, birthday calculator, quickconver
calculate age in years, months, and days for any as-of date. see total elapsed days and the next birthday, with explicit february 29 handling.
calorie deficit calculator, daily calorie gap, calorie surplus calculator, intake versus maintenance, quickconver
compare your observed daily calorie intake with estimated maintenance calories to see an arithmetic deficit or surplus. adult-only educational estimate, not a diet prescription.
sleep calculator, bedtime calculator, wake time calculator, adult sleep schedule, quickconver
calculate an adult bedtime from your desired wake time, or a wake time from bedtime. include expected time to fall asleep, with age-aware cdc guidance and no sleep-cycle promises.
maintenance calorie calculator, maintenance calories, daily energy needs, tdee estimate, quickconver
estimate adult maintenance calories and resting energy from age, equation coefficient, height, weight, and typical activity using mifflin-st jeor. no weight-loss target or diet plan.
circumference of a circle, circumference calculator, circle perimeter, radius to circumference, diameter to circumference, quickconver
calculate the circumference of a circle from its radius or diameter. convert results among millimeters, centimeters, meters, inches, and feet with a live formula check.
volume of a cylinder, cylinder volume calculator, cylindrical tank volume, radius height volume, diameter height volume, quickconver
calculate right circular cylinder volume from radius or diameter and height. convert cubic meters, liters, cubic centimeters, cubic feet, cubic inches, and us gallons.
area of a triangle, triangle area calculator, heron formula calculator, three sides triangle area, base height triangle area, quickconver
calculate triangle area from base and perpendicular height or three side lengths using heron’s formula. convert between square metric and us customary units with validation.
Kostenlose Finanz- und Geschäftswerkzeuge für Zinsen, Kredite, Gewinnmargen, Steuern, Gebühren, ROI und alltägliche Geschäftsplanung.
Kostenlose Baukostenrechner für Beton, Farbe, Fliesen, Bodenbeläge, Dach, Gipskarton, Kies und andere Baumaterialschätzungen.
Sie finden das Tool, das Sie benötigen, nicht? Lassen Sie es uns per E-Mail wissen, und wir prüfen, ob wir es hinzufügen.
[email protected]