100% Free - No Signup Required
Free Z-Score Calculator
Calculate z-scores to measure standard deviations from the mean.
Files Never Leave Your DeviceInstant ProcessingNo Watermarks
CalculateQuick Answer
Z-score = (value - mean) / standard deviation. Z=0 means at mean. Z=1 means 1 SD above. 68% within ±1, 95% within ±2.
Key Facts about Z-Score Calculator:
- Z = (value - mean) / SD
- Z = 0 means at the mean
- 68% within z = ±1
- 95% within z = ±2
- 99.7% within z = ±3
Why Use Our Z-Score Calculator?
Z-score tools:
📊
Calculate Z
From value or percentile.
📈
Percentile
Find percentile rank.
🔢
Probability
Normal distribution.
📐
Two-Way
Z to value or value to z.
⚡
Instant
Quick results.
🔒
Private
Data stays secure.
How to Z-Score Calculator in 3 Easy Steps
Calculate z-score:
1
Enter Values
Value, mean, SD.
2
Calculate
Compute z-score.
3
Interpret
See percentile.
📊
Z-Scores
Standard score calculation
Frequently Asked Questions
Everything you need to know about our z-score calculator
What does z-score mean?
Standard deviations from mean.
How many standard deviations a value is from the mean. Z=2 means 2 SDs above mean.
Still have questions? Try the tool yourself!
CalculateRelated Tools You Might Like
Explore more free tools to boost your productivity