# Clock time decrementer

World's simplest time toolWith this browser-based application, you can subtract any time interval from the given clock time. The time interval to be subtracted can be any hours, minutes, and seconds (specified in the options). The decremented time can be output in various formats (24-hour clock, 12-hour clock, text, or seconds) and if the clock goes back too much, you can control the time underflow using four underflow modes. Created by computer nerds from team Browserling.

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## What is a clock time decrementer?

learn more about this toolThis is a quick online utility for decrementing one or more clock times by any time amount. When time is decremented, the clock moves backward. There are many use-cases for this time operation. For example, if you had a great workout and recorded great sprint times but then noticed that there was a stopwatch measurement error of two seconds, then you can quickly and effortlessly subtract these 2 seconds from each recorded time. Another great use-case is making DST adjustments when the clock is moved back by one hour. Overall, you can subtract any number of seconds, minutes, and hours from a clock time (or multiple clock times). The interval that needs to be subtracted can be set in the options using several different formats. For example, the interval can be "2 hours", "5 minutes", "30 seconds", "1h 2m 3s", "8 hours 2 min", or "5:10:02". Each time to be decremented must be listed in the input field, one per line. You can use full or partial 24-hour and 12-hour time formats in the input. For example, good inputs are "20:30:00", "20:30", or "10:30 pm". When the time is shifted backward, it will appear in the output field. You can choose from a variety of time formats for the output, and display the time as a digital clock (24-hour and 12-hour formats), in absolute number of seconds, or as spelled text. A separate option can be used to control the scenario when time underflows. Underflow happens when you decrease midnight time by 1 second (or more). For example, if the current time is 00:00:05 (5 seconds past midnight) and you decrease this time by 10 seconds, then you'll get the previous day 23:59:55. The "Print Strict Time" underflow method will print "23:59:55". You can also mark the previous day (or days) via the "Mark Time Underflow" underflow method and you will get "23:59:55 (-1)". The "minus 1" here indicates that day changed by one day backwards. You can also enable negative time with the "Print Non-strict Time" method. Here, the new time will be printed with a minus sign and you'll get "-00:00:05". Finally, if you want the time to stop at midnight "00:00:00", use the "Stop Time at Midnight" method. If instead of decrementing time, you need to increment time, use our increment clock time program. Timeabulous!

## Clock time decrementer examples

Click to useSet Clocks Back by One Hour

In this example, we switch to wintertime and set all clocks back by one hour. In the options, we enter the interval equal to "1 hour" and activate the "Print Strict Time" option so that the time that's close to 00:00:00 keeps decreasing from 23:59:59.

10:20:30
06:00:00
20:50:00
14:40:04
00:30:00

09:20:30
05:00:00
19:50:00
13:40:04
23:30:00

**Required options**

Set the decrement interval.

Format for the decremented

time.

time.

Options to control time

behavior when it's decreased

below 00:00:00.

behavior when it's decreased

below 00:00:00.

Decrement 12-hour Time

In this example, we load a list of clock times in a 12-hour format and subtract 2 hours and 40 minutes from them. Since we have a non-strict time mode selected, times that underflow 00:00:00 become negative.

2 am
5 am
8 pm
10:40 am
9:45:50 pm

-0:40:0 am
2:20:0 am
5:20:0 pm
8:0:0 am
7:5:50 pm

**Required options**

Set the decrement interval.

Format for the decremented

time.

time.

Options to control time

behavior when it's decreased

below 00:00:00.

behavior when it's decreased

below 00:00:00.

Decrease the Time by More than a Day

In this example, we decrement the given time values by 25 hours, which is equal to one day and one hour. By subtracting such a large time interval, many of the time values underflow the midnight point (00:00:00). When such underflow happens, the day changes to one day in the past. To see how many days have passed, we activate the "Mark Time Underflow" mode, which shows in the parentheses how many days in the past each time ends up.

00:00
06:00
12:00
24:00
32:00

23:0:0 (-2)
5:0:0 (-1)
11:0:0 (-1)
23:0:0 (-1)
7:0:0

**Required options**

Set the decrement interval.

Format for the decremented

time.

time.

Options to control time

behavior when it's decreased

below 00:00:00.

behavior when it's decreased

below 00:00:00.

Decrease Time Within One Day

In this example, we shift several times backward by a custom interval and we disallow the times to be shifted beyond the boundaries of a single day. In other words, when the time reaches 00:00:00, the time freezes and no longer decreases. We shift all clocks back by 9 hours, 39 min, and 59 secs and to make it easier and quicker to write this interval in the options, we use the digital clock interval format "09:39:59" for it.

04:30:28
08:00:00
09:40:00
10:39:59

00:00:00
00:00:00
00:00:01
01:00:00

**Required options**

Set the decrement interval.

Format for the decremented

time.

time.

Options to control time

behavior when it's decreased

below 00:00:00.

behavior when it's decreased

below 00:00:00.

Spell Decremented Time

In this example, we paste a list of clock times in the input and subtract 1 minute from each time. The first clock time goes back from today to yesterday and the other times have overflow minutes (minutes counter is more than 60). The program converts all times into valid clock times and spells them in English in the output.

0:0
1:10
2:20
3:30
4:40
5:50
6:60
7:70
8:80
9:90

23 hours and 59 minutes
1 hour and 9 minutes
2 hours and 19 minutes
3 hours and 29 minutes
4 hours and 39 minutes
5 hours and 49 minutes
6 hours and 59 minutes
8 hours and 9 minutes
9 hours and 19 minutes
10 hours and 29 minutes

**Required options**

Set the decrement interval.

Format for the decremented

time.

time.

Options to control time

behavior when it's decreased

below 00:00:00.

behavior when it's decreased

below 00:00:00.

Pro tips Master online time tools

You can pass input to this tool via

__?input__query argument and it will automatically compute output. Here's how to type it in your browser's address bar. Click to try!https://onlinetools.com/time/decrement-clock-time

__?input__=10%3A20%3A30%0A06%3A00%3A00%0A20%3A50%3A00%0A14%3A40%3A04%0A00%3A30%3A00&interval=1%20hour&format=hh-mm-ss&time-overflow=strict-timeAll time tools

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Create a GIF animation of a clock that's broken.

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Draw a daily calendar for a single day.

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Draw a yearly calendar for the entire year.

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Draw a calendar that shows moon phases.

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Draw a calendar that shows the seasons and Sun's position.

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Draw an animation that counts down (or up) time.

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Visualize the given clock time as a pie chart.

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Animate Saturn's Moons

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Animate Uranus's Moons

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Animate Neptune's Moons

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Generate a list of invalid clock times (for testing).

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Generate Invalid Calendar Dates

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Quickly find how many days are left till a specific date.

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Find how many minutes are in the given seconds.

Convert Seconds To Hours

Find how many hours are in the given seconds.

Convert Seconds to Days

Find how many days are in the given seconds.

Convert Seconds to Weeks

Find how many weeks are in the given seconds.

Convert Seconds to Months

Find how many months are in the given seconds.

Convert Seconds to Years

Find how many years are in the given seconds.

Convert Minutes to Seconds

Find how many seconds are in the given minutes.

Convert Minutes To Hours

Find how many hours are in the given minutes.

Convert Minutes to Days

Find how many days are in the given minutes.

Convert Minutes to Weeks

Find how many weeks are in the given minutes.

Convert Minutes to Months

Find how many months are in the given minutes.

Convert Minutes to Years

Find how many years are in the given minutes.

Convert Hours To Seconds

Find how many seconds are in the given hours.

Convert Hours to Minutes

Find how many minutes are in the given hours.

Convert Hours to Weeks

Find how many weeks are in the given hours.

Convert Hours to Months

Find how many months are in the given hours.

Convert Hours to Years

Find how many years are in the given hours.

Convert Days to Seconds

Find how many seconds are in the given days.

Convert Days to Minutes

Find how many minutes are in the given days.

Convert Days to Weeks

Find how many weeks are in the given days.

Convert Days to Months

Find how many months are in the given days.

Convert Days to Years

Find how many years are in the given days.

Convert Weeks to Seconds

Find how many seconds are in the given weeks.

Convert Weeks To Minutes

Find how many minutes are in the given weeks.

Convert Weeks To Hours

Find how many hours are in the given weeks.

Convert Weeks to Days

Find how many days are in the given weeks.

Convert Weeks to Months

Find how many months are in the given weeks.

Convert Weeks to Years

Find how many years are in the given weeks.

Convert Months to Seconds

Find how many seconds are in the given months.

Convert Months To Minutes

Find how many minutes are in the given months.

Convert Months To Hours

Find how many hours are in the given months.

Convert Months to Days

Find how many days are in the given months.

Convert Months to Weeks

Find how many weeks are in the given months.

Convert Months to Years

Find how many years are in the given months.

Convert Years to Seconds

Find how many seconds are in the given years.

Convert Years To Minutes

Find how many minutes are in the given years.

Convert Years To Hours

Find how many hours are in the given years.

Convert Years to Days

Find how many days are in the given years.

Convert Years to Weeks

Find how many weeks are in the given years.

Convert Years to Months

Find how many months are in the given years.

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Find how old a human would be if he/she was a bird.

Convert a Human's Age to Bird Years

Find how old a bird would be if it was a human.

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Convert clock time on Earth to clock time on Mars.

Convert Mars Time to Earth Time

Convert clock time on Mars to clock time on Earth.

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Print a list of clock times with hours equal mins equal secs.

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Print a list of all clock times when hands are in a straight line.

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Given calendar dates in various formats, make them the same format.

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Perform freeform clock time arithmetics.

Freeform Date Calculator

Perform freeform calendar date arithmetics.

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Find the sum of years plus months plus days.

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Find clock hand position so that hr + min + sec equals your value.

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Find calendar date so that year + months + day equals your value.

Generate Clock Emojis

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Create Zalgo Time

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"4 hours", "1 hour 2 min 40 sec"

"10 minutes", or "05:15:40".