BC to AD Calculator

How to Calculate Time Between BC and AD Years

Calculating the amount of time between two years can be tricky, but with AD and BC years it can seem even more tricky. To easily calculate the years between a BC and AD years, you can employ this formula:

Understanding Your Results

With our AD to BC tool, the results simply is the number of total years between the two years. Since the years are spanning between two different classifications of time, it can be difficult and confusing to do the math yourself. Our tool easily does this math for you and will display the number of years between your AD and BC years that you entered.

How to Use the BC to AD Calculator

Use this tool if you want to simply find the number of years between two different years. The steps involved with using our tool includes:

1. Enter the BC/BCE year into the first field.


2. Enter the AD/CE year into the second field if it differs from the current year that is already entered into the field.


3. Hit calculate and almost instantly get your difference in years between the two years you entered. Feel free to convert that to smaller units of time by choosing another option from the dropdown menu next to your answer.

Calculation Examples

Let's say you want to calculate the amount of years between the current year, 2024, and 1550 BC. First you would enter 1550 into the BC field and then leave the AD field alone as it will already say 2024 (if the current year is 2024). Hit calculate and you will get your answer of 3,574 years. You can then change that value to be months or another measure of time if you need.

Alternatively, you could do that math manually. You would do the following math: 1550 + 2024 to get the answer of 3,574 years between the two years. Converting that into months and other units of time measurement manually would be slightly more difficult but is still doable.