P-value ≥ α → fail to reject H₀ (insufficient evidence).
A P-value of 0.03 at α = 0.05 means the result is significant. At α = 0.01, it is not.
A two-tailed test (P = 2 × P_one-tail) is conservative and standard for most tests with no directional hypothesis.
How to interpret your results?
P-value meaning
The probability of observing a test statistic as extreme as (or more extreme than) the one computed, assuming H₀ is True. A small P-value means your result is unlikely under H₀.
Common misconception
The P-value is not the probability that H₀ is True. It is the probability of the data given H₀. 'P = 0.05' does not mean 95% chance the result is real.
Frequently asked questions
How do I use the P Value Calculator calculator?
Enter your numerical input and select desired units to get instant accurate results.
How accurate are the conversions?
Conversions use official ISO conversion factors for maximum precision.
Does it convert metric and imperial units?
Yes, seamless conversions between metric (meters, kg) and imperial (feet, lbs) are supported.
Is my data stored?
No, all calculations execute 100% locally in your browser with zero data logging.
Can I use this for DIY or engineering projects?
Yes, it provides reliable estimates for construction, crafting, science, and everyday math.
What if I enter invalid inputs?
The calculator will display a friendly error prompt if non-numeric values are entered.
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