Chemistry

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Carbon Dating Calculator.

Estimate radiocarbon age from remaining fraction and an explicit isotope half-life.

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Set your values

Results update as you type.

02 / ANSWER

Fraction remaining

Half-life

Estimated age

5,730.000000years

Decay constant

0.0001211/year

Educational chemistry arithmetic only. Keep units consistent and verify assumptions against your laboratory or course specification.

Use Cases

Archaeological dating

Estimate the age of organic artifacts by measuring the remaining carbon-14 fraction and using the standard half-life.

Example: A wooden tool with 25% carbon-14 remaining would be about 11,460 years old (using 5,730-year half-life).

Educational demonstration

Teach radioactive decay concepts by varying the half-life and fraction to see how age changes.

Example: Set half-life to 1,000 years and fraction to 0.5 to see an age of 1,000 years.

Frequently Asked Questions

How does the carbon dating calculator work?: It uses the radioactive decay formula: age = (half-life / ln(2)) * ln(1 / fraction remaining). You input the fraction of carbon-14 remaining and the half-life (in years) to get the estimated age.
What is the half-life of carbon-14?: The commonly used half-life for carbon-14 is 5,730 years. However, the calculator allows you to enter any half-life value, so you can use the standard value or a different one if needed.
What does 'fraction remaining' mean?: It is the proportion of the original radioactive isotope that remains in the sample. For example, if 50% remains, enter 0.5. The calculator uses this to determine how many half-lives have passed.

Tips & Common Mistakes

Tips

Ensure the fraction remaining is between 0 and 1 (e.g., 0.5 for 50%).
Use the standard carbon-14 half-life of 5,730 years for most archaeological samples.
Double-check your units: half-life must be in years to get age in years.
For very small fractions, the age becomes large; verify your input is realistic.

Common Mistakes to Avoid

Entering percentage (e.g., 50) instead of fraction (0.5).
Using the wrong half-life for the isotope being dated.
Confusing the formula: age increases as fraction remaining decreases, so check your result makes sense.

Last updated: August 13, 2026

Use Cases

Archaeological dating

Estimate the age of organic artifacts by measuring the remaining carbon-14 fraction and using the standard half-life.

Example: A wooden tool with 25% carbon-14 remaining would be about 11,460 years old (using 5,730-year half-life).

Educational demonstration

Teach radioactive decay concepts by varying the half-life and fraction to see how age changes.

Example: Set half-life to 1,000 years and fraction to 0.5 to see an age of 1,000 years.

Frequently Asked Questions

How does the carbon dating calculator work?

It uses the radioactive decay formula: age = (half-life / ln(2)) * ln(1 / fraction remaining). You input the fraction of carbon-14 remaining and the half-life (in years) to get the estimated age.

What is the half-life of carbon-14?

The commonly used half-life for carbon-14 is 5,730 years. However, the calculator allows you to enter any half-life value, so you can use the standard value or a different one if needed.

What does 'fraction remaining' mean?

It is the proportion of the original radioactive isotope that remains in the sample. For example, if 50% remains, enter 0.5. The calculator uses this to determine how many half-lives have passed.

Tips & Common Mistakes

Tips

Ensure the fraction remaining is between 0 and 1 (e.g., 0.5 for 50%).
Use the standard carbon-14 half-life of 5,730 years for most archaeological samples.
Double-check your units: half-life must be in years to get age in years.
For very small fractions, the age becomes large; verify your input is realistic.

Common Mistakes to Avoid

Entering percentage (e.g., 50) instead of fraction (0.5).
Using the wrong half-life for the isotope being dated.
Confusing the formula: age increases as fraction remaining decreases, so check your result makes sense.

Use Cases

Archaeological dating

Estimate the age of organic artifacts by measuring the remaining carbon-14 fraction and using the standard half-life.

Example: A wooden tool with 25% carbon-14 remaining would be about 11,460 years old (using 5,730-year half-life).

Educational demonstration

Teach radioactive decay concepts by varying the half-life and fraction to see how age changes.

Example: Set half-life to 1,000 years and fraction to 0.5 to see an age of 1,000 years.

Frequently Asked Questions

How does the carbon dating calculator work?

It uses the radioactive decay formula: age = (half-life / ln(2)) * ln(1 / fraction remaining). You input the fraction of carbon-14 remaining and the half-life (in years) to get the estimated age.

What is the half-life of carbon-14?

The commonly used half-life for carbon-14 is 5,730 years. However, the calculator allows you to enter any half-life value, so you can use the standard value or a different one if needed.

What does 'fraction remaining' mean?

It is the proportion of the original radioactive isotope that remains in the sample. For example, if 50% remains, enter 0.5. The calculator uses this to determine how many half-lives have passed.

Tips & Common Mistakes

Tips

Ensure the fraction remaining is between 0 and 1 (e.g., 0.5 for 50%).
Use the standard carbon-14 half-life of 5,730 years for most archaeological samples.
Double-check your units: half-life must be in years to get age in years.
For very small fractions, the age becomes large; verify your input is realistic.

Common Mistakes to Avoid

Entering percentage (e.g., 50) instead of fraction (0.5).
Using the wrong half-life for the isotope being dated.
Confusing the formula: age increases as fraction remaining decreases, so check your result makes sense.