Z-Score Calculator
Calculate the Z-score (standard score) for a value given the mean and standard deviation. See the percentile and interpretation.
How to Use the Z-Score Calculator
- Enter your data set or statistical values in the input fields.
- Click Calculate to process the data.
- Review the computed result with detailed breakdown.
- Modify inputs or add more data points for further analysis.
مرجع سريع
| من | إلى |
|---|---|
| Mean [2,4,6] | 4 |
| Median [1,3,5,7] | 4 |
| Mode [2,2,3,5] | 2 |
| σ [2,4,4,4,5,5,7,9] | 2 |
| z-score (x=85, μ=70, σ=10) | 1.5 |
| P(A)+P(B)−P(A∩B) | P(A∪B) |
حالات الاستخدام
- •Analyzing data sets for research papers or school projects.
- •Checking statistical calculations before including them in reports.
- •Understanding data distributions and variability in experiments.
- •Making data-driven decisions in business or academic contexts.
الصيغة
Z = (X − μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation.
الأسئلة الشائعة
What is a Z-score?
A Z-score tells you how many standard deviations a value is from the mean. A Z-score of 0 means the value equals the mean.
What does a negative Z-score mean?
A negative Z-score means the value is below the mean. For example, Z = −2 means the value is 2 standard deviations below the mean.
How is the percentile related to the Z-score?
The percentile tells you the percentage of values in a normal distribution that fall below your Z-score. Z = 0 corresponds to the 50th percentile.
What is a typical range for Z-scores?
In a normal distribution, about 99.7% of values fall within Z = −3 to Z = +3. Values beyond ±3 are rare outliers.