Time Percentage Calculator
Find what percentage of a day, week, month, or year has passed — or calculate a specific point in time from a percentage. Useful for progress tracking and planning.
How to Use
- Choose a mode: "Time → Percentage" tells you how far through a period you are. "Percentage → Time" tells you when a given percentage point occurs.
- Select the time period: Day (24 hours), Week (7 days), Month (30 days), or Year (365 days).
- Enter the time or percentage: For "Time → Percentage", enter hours (for a day) or days (for week, month, year). For "Percentage → Time", enter the target percentage (0–100).
- Read the results: See elapsed percentage, remaining percentage, and remaining time instantly.
What You'll Discover
- Percentage elapsed — in Time → Percentage mode, how much of a day, week, month or year has passed: time elapsed ÷ total × 100.
- Percentage remaining — 100% minus the elapsed share.
- Time remaining — what is left of the period, in hours for a day and in days for a week, month or year.
- Time at a percentage — in Percentage → Time mode, how many hours or days into the period a given percentage falls, plus the time still remaining after it.
The tool uses fixed lengths: 24 hours, 7 days, 30 days and 365 days. Decimals are fine, so 14.5 hours means 2:30 PM. If you enter more time than the period holds, the result is capped at 100% elapsed and 0 remaining.
Formula
Time to Percentage
% Elapsed = (Time Elapsed / Total Duration) × 100
For a day: % elapsed = (hours elapsed / 24) × 100. For a week, month or year: % elapsed = (days elapsed / total days) × 100.
Percentage to Time
Time = (Percentage / 100) × Total Duration
For 50% of a year: (50 / 100) × 365 = 182.5 days elapsed.
Period Durations Used
- Day: 24 hours
- Week: 7 days
- Month: 30 days (standard approximation)
- Year: 365 days (non-leap year standard)
Examples
Example 1 — Progress through the day
It is 3:00 PM (15:00), so 15 hours have passed in a 24-hour day. Percentage elapsed: (15 / 24) × 100 = 62.5% of the day. Remaining: 37.5% = 9 hours left.
Example 2 — Year progress
Day 100 of the year: (100 / 365) × 100 ≈ 27.4% of the year has passed. Remaining: 265 days (72.6%).
Example 3 — Project deadline
A 30-day project: after 18 days you are (18 / 30) × 100 = 60% through the month. You have 12 days remaining.
Example 4 — Finding the 75% point
75% of a week: (75 / 100) × 7 = 5.25 days into the week. If your week starts Monday at midnight, five full days (Monday to Friday) have passed, so the 75% point is 6:00 AM on Saturday.
Converting Clock Time and Mixed Units
The most common mistake with time percentages is treating minutes as decimals. 1 hour 30 minutes is 1.5 hours, not 1.3. Convert everything to one unit before you divide.
Minutes to decimal hours
Divide the minutes by 60 and add them to the hours. 2:30 PM is 14 + 30 ÷ 60 = 14.5 hours, which is (14.5 ÷ 24) × 100 ≈ 60.42% of the day. 1 hour 25 minutes is 1 + 25 ÷ 60 ≈ 1.4167 hours.
Comparing any two durations
The same formula works for any part and whole, as long as both use the same unit. A 1 hour 25 minute task out of a 3 hour 30 minute block is 85 ÷ 210 × 100 ≈ 40.48% when both are in minutes. A 90-minute meeting in an 8-hour workday is 1.5 ÷ 8 × 100 = 18.75%.
Decimal hours back to clock time
In Percentage → Time mode with Day selected, the result is in decimal hours. Multiply the decimal part by 60 to get minutes. 40% of a day is 9.6 hours, and 0.6 × 60 = 36, so the 40% point is 9:36 AM.
| Time of day | Hours elapsed | % of day elapsed |
|---|---|---|
| 1:00 AM | 1 | 4.17% |
| 6:00 AM | 6 | 25% |
| 8:00 AM | 8 | 33.33% |
| 9:00 AM | 9 | 37.5% |
| 12:00 PM (noon) | 12 | 50% |
| 2:30 PM | 14.5 | 60.42% |
| 3:00 PM | 15 | 62.5% |
| 6:00 PM | 18 | 75% |
Percentage of the Year: Day Numbers, Months and Leap Years
For the year, enter the day-of-year number, which counts days from January 1. The table shows how much of a non-leap year has passed at the end of selected months.
| End of | Day of year | % of year elapsed |
|---|---|---|
| January | 31 | 8.49% |
| February | 59 | 16.16% |
| March | 90 | 24.66% |
| June | 181 | 49.59% |
| September | 273 | 74.79% |
| October | 304 | 83.29% |
| November | 334 | 91.51% |
| December | 365 | 100% |
Notice that the end of June is just under half the year, because January to June has 181 days and the halfway point is day 182.5.
Leap years
A leap year has 366 days. The calculator always divides by 365, so in a leap year work the figure by hand: day number ÷ 366 × 100. February 29 is day 60, which is 60 ÷ 366 × 100 ≈ 16.39% of a leap year. From March onward, each day number is also one higher than in a common year.
Real calendar months
The Month option uses 30 days. For an exact answer in a 31-day or 28-day month, divide the days elapsed by that month's real length. Day 15 of a 31-day month is 15 ÷ 31 × 100 ≈ 48.39%, not 50%.
What Percentage Has Passed If...
What percentage of the day has passed if it is 9:00 AM?
At 9:00 AM, 37.5% of the day has passed. 9 hours have elapsed, and 9 ÷ 24 × 100 = 37.5%. 15 hours, or 62.5%, remain.
What percentage of the day has passed if it is 2:30 PM?
At 2:30 PM, about 60.42% of the day has passed. 2:30 PM is 14.5 hours after midnight, and 14.5 ÷ 24 × 100 ≈ 60.42%.
What percentage of my day is an 8-hour workday?
An 8-hour workday is one third of a 24-hour day, about 33.33%. Over a week, 40 working hours are 40 ÷ 168 × 100 ≈ 23.81% of all the hours in the week.
What percentage of the week has passed if it is Wednesday at noon?
If your week starts Monday, Wednesday at noon is about 35.71% of the way through the week. Monday, Tuesday and half of Wednesday make 2.5 days, and 2.5 ÷ 7 × 100 ≈ 35.71%. Enter 2.5 with Week selected.
What percentage of the month has passed if it is day 15?
Using a 30-day month, 15 days is exactly 50%. In a 31-day month, 15 days is about 48.39%; in February (28 days) it is about 53.57%.
What percentage of the year has passed at the end of March?
At the end of March in a common year, about 24.66% of the year has passed. January to March has 90 days, and 90 ÷ 365 × 100 ≈ 24.66%.
What percentage of the year has passed on November 7?
November 7 is day 311 of a common year, which is about 85.21% of the year. 311 ÷ 365 × 100 ≈ 85.21%, with 54 days (about 14.79%) left.
What percentage of a leap year has passed on February 29?
February 29 is day 60 of 366, about 16.39% of a leap year. The calculator uses 365 days, so do this one by hand: 60 ÷ 366 × 100 ≈ 16.39%.
What time is it when 40% of the day has passed?
40% of the day falls at 9:36 AM. 0.40 × 24 = 9.6 hours, and 0.6 hours is 36 minutes.
What percentage of an hour is 45 minutes?
45 minutes is 75% of an hour. 45 ÷ 60 × 100 = 75%. The calculator's shortest period is a day, so use this formula for parts of an hour; as decimal hours, 45 minutes is 0.75.
People Also Search For
How to calculate the percentage of time
Divide the part of the time by the total time, using the same unit for both, and multiply by 100. 2 hours out of 8 is 2 ÷ 8 × 100 = 25%. If one value is in minutes and the other in hours, convert first.
How to convert minutes to a percentage of an hour
Divide the minutes by 60 and multiply by 100. 15 minutes is 25%, 20 minutes is about 33.33%, and 30 minutes is 50%. Payroll systems often record these as decimal hours: 0.25, 0.33 and 0.5.
What percentage of the year is left?
Subtract the elapsed percentage from 100%, or divide the days remaining by 365. On day 311 of a common year, 54 days remain, which is about 14.79% of the year.
How to calculate the percentage of time spent on a task
Divide the time spent on the task by the total time available, in the same unit. A 90-minute meeting in an 8-hour (480-minute) workday is 90 ÷ 480 × 100 = 18.75%.
How to convert a percentage of a day to hours
Multiply the percentage by 24 and divide by 100. 25% of a day is 6 hours, 37.5% is 9 hours, and 75% is 18 hours (6:00 PM).
Time elapsed vs work completed
If more of the timeline has passed than of the work is done, the project is behind schedule. On day 18 of a 30-day project, 60% of the time is used. If only half the tasks are done, the work is 10 percentage points behind.
Frequently Asked Questions
What percentage of the year has passed today?
Use the "Time → Percentage" tab, select "Year", and enter the day number of the current year (e.g. January 31 = day 31, February 28 = day 59 in non-leap years). Divide by 365 and multiply by 100 for the percentage. The formula is: day number / 365 × 100. In a leap year, divide by 366 instead.
How do I use this for project deadlines?
Select "Month" or "Week" depending on your project duration. Enter the number of days elapsed. The result shows what percentage of the timeline is complete and how many days remain. Compare this with your actual task completion percentage — if timeline% exceeds task%, you are behind schedule.
Why does the month use 30 days instead of the actual calendar month?
This calculator uses 30 days as a standard approximation for a month because calendar months vary from 28 to 31 days. Using 30 makes it straightforward to compare months without needing to know which specific month you are in. For exact calculations within a specific calendar month, divide by the actual number of days in that month.
How do I find what time 25% through the day is?
Use the "Percentage → Time" tab, select "Day", and enter 25. The result is (25 / 100) × 24 = 6 hours into the day, which is 6:00 AM. Similarly, 50% = noon (12:00), 75% = 6:00 PM, and 100% = midnight at the end of the day.
Can I use this to track percentage of a work week?
The Week option uses 7 days. For a 5-day work week, divide by 5 instead: after 3 of 5 working days you are 60% through the work week. Alternatively, use "Month" for monthly project tracking or "Year" for annual goals.
How do I enter hours and minutes?
Enter decimal hours. Divide the minutes by 60 and add them to the hours: 2:30 PM is 14.5, 9:45 AM is 9.75, and 6:20 PM is about 18.33.
What happens if I enter more time than the period has?
The calculator caps the result at 100% elapsed, 0% remaining and 0 time remaining. For example, 30 hours in a day still shows 100%. To compare a duration longer than the period, divide it by the total by hand; the answer will be above 100%.
Does the calculator handle leap years?
No. The Year option always uses 365 days. In a leap year, divide the day number by 366. The difference is small: on day 60, 60 ÷ 365 is about 16.44% and 60 ÷ 366 is about 16.39%.
Can I find a percentage of time for periods like an hour or a semester?
Not directly, since the periods are fixed to a day, week, 30-day month and 365-day year. Use the formula instead: elapsed ÷ total × 100. Week 6 of a 15-week semester is 6 ÷ 15 × 100 = 40%.
Is my data stored or sent anywhere?
No. All calculations run in your browser. Nothing you type is sent to a server or saved, and no account is needed.
Last reviewed: November 2026 — formulas and worked examples verified.