Asteroid Hit Odds Calculator
Example: 116 m² = 1 in 2.2T odds
What are the chances of an asteroid crashing through your roof? This calculator uses published data to estimate the annual probability of an asteroid strike on a specific property. The estimated odds for a typical house footprint are approximately 1 in 2.2 trillion.
Your odds vs everyday risks (1 in N, log scale)
Annual Odds
Chance per year (1 in X)
Probability
As a decimal probability
Comparison
How this compares to other risks
Fun Fact
How We Calculate This
Annual probability = footprint area × strike rate per m² per year. The strike rate (≈3.92e-15) is calibrated from cited odds of 1 in 2.2 trillion for a 116 m² footprint. Results are presented as "1 in X" format.
Methodology last reviewed: May 2025. How SparkCalc works
Sources: NASA: Asteroid Fast Facts (impact frequency by size) · NASA CNEOS: Sentry: Earth Impact Monitoring
Frequently Asked Questions
Where do these odds come from?
The calculation is calibrated from a cited example where a 1,250 ft² (116 m²) house footprint has annual odds of 1 in 2,196,269,636,024 of being hit by an asteroid. We derive a per-square-meter rate from this.
Is this a real risk I should worry about?
No! At 1 in trillions per year, an asteroid hitting your specific house is essentially impossible in any human timeframe. You're far more likely to win the lottery multiple times. This calculator is purely for entertainment.
What about larger asteroids hitting Earth generally?
Larger asteroid impacts affecting wide areas are more likely but still rare. NASA tracks near-Earth objects and estimates a civilization-threatening impact happens roughly once every 500,000+ years.
Has a building ever been hit by a meteorite?
Yes! Small meteorites have struck buildings, including the famous Sylacauga meteorite in 1954 that went through a roof and injured Ann Hodges. But these are small fragments, not catastrophic asteroids.
Related Calculators
You might also find these calculators helpful: Square Footage Calculator, and Statistics Calculator.
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This calculator is for entertainment purposes only. While based on cited calculations, asteroid impact probability involves many complex factors. Do not use for actual risk assessment or insurance purposes.