How do archaeologists know a wooden artifact is 3,000 years old and not 300? The answer is ticking inside every living thing: cosmic rays constantly create carbon-14 in the atmosphere, plants absorb it, animals eat the plants, and while an organism lives, its carbon-14 ratio stays steady. At death the intake stops and the clock starts — carbon-14 decays with a half-life of about 5,730 years, so measuring what fraction remains reveals how long ago the organism died. The math is exponential decay: age = -(1/λ) × ln(remaining fraction), where λ is the decay constant. If half the carbon-14 is gone, one half-life (5,730 years) has passed; if a quarter remains, two have. The method works back roughly 50,000 years before the signal gets too faint. This calculator runs the decay arithmetic: enter your values in the Variable A and Variable B fields and read the Result. Contamination and atmospheric variation add real-world uncertainty, which is why labs calibrate against tree-ring data — but the exponential core is beautifully simple.

With the pre-filled defaults — Variable A 10, Variable B 5 — the Carbon Dating Calculator returns Result 50.0000. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.