Sobriety Calculator + Online Solver With Free Steps

The Sobriety Calculator determines the duration of time for which a person has been clean and sober, given the date they started fighting against their addiction (sometimes called the sobriety date). 

Addiction to drugs and alcohol is not an easy thing to let go of. This calculator aims to provide a consistent source of encouragement and confidence to recovering addicts by allowing them to define and track their progress and remind them of the time they have succeeded in remaining sober and clean. 

Most recovery programs believe in the significance of marking time for recovering addicts – they find it serves as a source of daily reprieve, urging them to continue with their struggle.

sobriety calculator

What Is the Sobriety Calculator?

The Sobriety Calculator is an online tool that calculates how long an alcoholic or drug addict has been sober and clean. 

The calculator interface consists of a specified text box labeled “Clean and Sober since,” in which the user enters the date an addict started their recovery process. After that, the calculator finds the length of their sobriety in terms of years, months, days, and weeks.

How To Use the Sobriety Calculator?

You can use the Sobriety Calculator to find the length of time a recovering addict has been sober by entering the starting time of their recovery process.

Suppose you want to find the sobriety period for someone who claims to have been sober since the 6th of April, 2007. Then you can use the calculator for this by following these step-by-step guidelines below.

Step 1

Enter the date since the person has been sober into the text box labeled “Clean and Sober since.” For the example above, you would type “06-04-2007” without quotes. 

You could also type “06 04 2007,” “06.04.2007,” “Sixth April, Two Thousand and Seven,” or “April 6, 2007,” etc. They all mean the same thing to the calculator.

Step 2

Press the Submit button to get the results.


The results show in a new pop-up window and consist of three sections.

  1. Input Interpretation: This section contains the input as interpreted by the calculator. It allows manual verification of the user input.
  2. Result: The duration of sobriety in terms of years, months, and days. It is the main result of the calculator.
  3. Time Span: The sobriety period is purely one or, at most, two units of time, such as only in years, weeks, months, etc.

For our mock example above, the results are:

Input Interpretation: Friday, April 6, 2007, to today (Aug 19, 2022).

Result: 15 years, 4 months, 13 days.

Time Span: 802 weeks, 5614 days, 15.37 years.

Valid Date Formats

The only requirement is that the input contains the date, month, and year. The order does not matter, so YYYY-MM-DD is as valid as DD-MM-YYYY. It also does not matter if you use words, numbers, or a combination of both to express the date. You may also abbreviate the month names (“Apr” for April). 

However, if you only use numbers, the calculator might get confused between MM-DD-YYYY and DD-MM-YYYY formats. For example, the calculator cannot tell which is the month and which is the day between 04-06-2007 and 06-04-2007. In such confusing cases, it assumes the DD-MM-YYYY format in the calculations. 

If the calculator encounters a value greater than 12 in a particular part of the input, it assumes it is the month. For example, in 06-13-2007, it will use the MM-DD-YYYY format because 13 > 12 and cannot be a month, meaning the date June 13, 2007. The same result appears for 13-06-2007, but this time the calculator interprets the date as DD-MM-YYYY. 

How Does the Sobriety Calculator Work?

The Sobriety Calculator works by calculating the total day count from the sobriety date until today, splitting it into years, months, and days for the final result.

Calculating date differences can be complex, but working through an example is the best way to understand how it works. Please view the solved examples section at the end to further your understanding of this calculator!

Months With Different Day Counts

To accurately count the number of days, the calculator does not just approximate 30 days per month. It looks up the exact number of days a month has and uses them in calculating the final result (see days count in the Time Span section of the results). 

We give the day count against each month below:

  • January: 31
  • February: 28 (29 on leap years)
  • March: 31
  • April: 30
  • May: 31
  • June: 30
  • July: 31
  • August: 31
  • September: 30
  • October: 31
  • November: 30
  • December: 31

Leap Years

A leap year is any year that is divisible by 4, and if it is a multiple of 100, then additionally divisible by 400. These years are significant because they contain 366 days instead of the usual 365 on a common year (29 days instead of 28 in February during a leap year).

For example, 2012 is a leap year because 2012 $\div$ 4 = 503. The year 2000 is a multiple of 100, and it is a leap year because it is divisible by both 4 (2000 $\div$ 4 = 500) and 400 (2000 $\div$ 400 = 5).

However, 1800 is not a leap year because, while it is divisible by 4 (1800 $\div 4 = 450), it is also a multiple of 100 BUT not divisible by 400.

Leap years are needed because our year of 365 days is only a rounded-down approximation of the actual solar year (roughly 365 days and 6 hours, or 365.25 days, which is the time it takes the Earth to complete a rotation around the Sun). Leap years have 366 days, and make up for the inaccuracy caused by this approximation. 

Note that the logic behind the “divisible by 400” condition is that a solar year is not exactly 365.25 days – it is slightly less at 365.2422 days. These two rules combined make the average number of days a year = 365.2425 days, much closer to 365.2422 days!

Accounting for Leap Years

During calculations, the calculator accounts for leap years by adding an extra day for every leap year’s 29$^\mathsf{th}$ February passed from the sobriety date till the current date. 

To see this, consider that the current date is 19-08-2022. Assume the sobriety date was 19-08-2018. 2020 is the leap year in between. The calculator outputs a result of 4 years and a total day count of 1461 days in the Time Span section. However, notice that 365 x 4 = 1460, so clearly the extra day came from the leap year’s February 29 as 365 x 3 + 366 = 1461 days.

Solved Examples

Example 1

Jesse Pinkman, after a series of unfortunate personal events owing to his drug addiction, has decided to join an addiction recovery program. As part of the program, he logged his sobriety date into the system of recovering addicts in the facility – September 13, 2010.

Mr. Pinkman has since followed the program closely and successfully stayed away from drugs of any kind. How long has he been clean if today is August 19, 2022?


First, let us count the years. 2022 – 2010 = 12 years, but since August comes before September, the actual year count is slightly less than 12, so we set it to 11.

Eleven years from September 13, 2010, would be September 13, 2021. From then on, we have the 3 months of October, November, and December for 2021. Then, for 2022, we have 8 months up to August. So 3 + 8 = 11 months. Since the final date is 19 > the initial date 13, we settle on 11 as the final month count.

Finally, we need the day count. Since the final date is greater than the initial date, we simply subtract the two to get 19 – 13 = 6.

Now, we can present our result in the final form: 

Sobriety Period = 11 years, 11 months, and 6 days

Years Only

We can convert the result to years by noticing that we have 11 months and 6 days – this means that we are on the 6$^\mathsf{th}$ day of the 12$^\mathsf{th}$ month. Since month 12 is December, and we have 31 days in December, we have 11 + (6 / 31) = 11.193 months in the final year, or 11.193 / 12 = 0.93275 years. So, we have a total of:

11 + 0.93275 $\boldsymbol{\approx}$ 11.932 years 

Days Only

11.932 x 365 = 4355 days

Accounting for leap days, we have three leap days (Feb 29 of the years 2012, 2016, and 2020) between September 2010 and August 2022. So we add 3 to the result above:

4355 + 3 = 4358 days

From here, we can get it in weeks:

4358/7 weeks = 622.57 weeks = 622 weeks + (0.57 * 7 days) = 622 weeks 4 days

So Mr. Pinkman has been sober and clean for 11 years, 11 months, and 6 days. Quite an achievement!

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