The significant figures counter is a tool which helps you calculate the number of significant figures in a given number. This calculator is very helpful for students, teachers, scientists and engineers who need to ensure their calculations are error-free and precise.

Significant figures also known as sig figs are the important digits in a number. A significant number shows how precise a number is. In simple terms, significant figures tell us which numbers in a value are important and which ones are just placeholders. For example: 12.34 has 4 significant figures because all non-zero numbers count.

To calculate the significant figures in a given number you need to follow a set of simple rules. Here is the breakdown of those rules:

Rule 1: Non-zero digits are always significant. This means any digits from 1 to 9 are always counted as significant. Example: In the number 345 all three digits (3, 4, and 5) are significant.
Rule 2: Zeros between significant numbers are counted as significant. If a zero is in-between two non-zero digits, it is considered significant. Example: in the number 601, the zero is significant because it is between 6 and 1.
Rule 3: Zeros at the start of a number are not significant. Leading zeros are just placeholders and don’t add any meaningful information. Example: in 0.005 only the 5 is significant.
Rule 4: Trailing zeros (zeros at the end of a number) are significant only if there is a decimal point. If the number has no decimal point, those zeros are not considered significant. Example: 800 — the zeros are not significant unless it is written as 800.
Rule 5: Exact numbers (counted values or defined values) have infinite significant figures. Example: if you count 100 chairs, the number 100 has infinite significant figures because it is an exact count.

There is no specific formula to calculate significant figures. You can use the above rules to analyse the number. Write down the number you want to analyse. carefully look at each digit and decide whether it is significant or not based on the above rule and count all the digits that are really significant.

Enter the number you want to calculate in the provided input field and click the calculate button. This calculator will instantly provide the results. This also shows which numbers are significant figures. This counter is very helpful when you are dealing with a very large number where calculating significant figures can be tricky.