สถิติ เครื่องคิดเลข
Mean, median, mode, standard deviation and more. Instant result with formula, examples and step-by-step calculation. Free online calculator.
เครื่องคิดเลข สถิติ ทั้งหมด
Mean Median Mode
Calculate central tendency measures. Step-by-step solution with formula, example dataset and interpretation guide.
Standard Deviation
Calculate variance and standard deviation. Step-by-step solution with formula, example dataset and interpretation guide.
Confidence Interval Calculator
Calculate confidence intervals for population means. Step-by-step solution with formula, example dataset and interpretation guide.
Test Grade Calculator
Convert correct answers to percentage and letter grade. Fast and accurate result with formula, step-by-step method and unit overview. Free tool.
Average Calculator
Find the arithmetic mean of numbers. Instant result with formula, worked example and step-by-step solution. No signup required.
Quartile Calculator
Calculate quartiles and IQR. Step-by-step solution with formula, example dataset and interpretation guide.
Percentile Calculator
Find percentile rank of data values. Step-by-step solution with formula, example dataset and interpretation guide.
Variance Calculator
Calculate statistical variance. Step-by-step solution with formula, example dataset and interpretation guide.
Z-Score Calculator
Calculate Z-scores and probabilities. Step-by-step solution with formula, example dataset and interpretation guide.
Descriptive Statistics
Complete statistical summary of a dataset. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Sum Calculator
Add a list of numbers quickly. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Random Number Generator
Generate random numbers in any range. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Random Name Picker
Pick random names from a list. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Coin Flipper
Flip a fair coin and track results. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Grade Calculator
Calculate class grades and GPA. Instant result with formula, worked example and step-by-step solution. No signup required.
GPA Calculator
Calculate Grade Point Average. Instant result with formula, worked example and step-by-step solution. No signup required.
Vote Percentage Calculator
Calculate voting percentages and results. Quick calculation with worked example and formula. Free everyday calculator.
Stem and Leaf Plot
Generate stem-and-leaf plots from data. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Sample Size Calculator
Required sample size for surveys. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Margin of Error
Margin of error for surveys. Instant result with amortization table, formula and chart. Free financial calculator.
Chi-Square Test
Chi-square goodness-of-fit statistic. Step-by-step solution with formula, example dataset and interpretation guide.
Two-Sample t-Test
Compare means of two independent groups. Step-by-step solution with formula, example dataset and interpretation guide.
Pearson Correlation
Linear correlation coefficient r. Step-by-step solution with formula, example dataset and interpretation guide.
Spearman Correlation
Spearman rank correlation rs. Step-by-step solution with formula, example dataset and interpretation guide.
R-squared Calculator
Coefficient of determination R². Formula, variable legend, diagram and worked example included. Instant geometry result.
Cohen's d Effect Size
Standardised effect size for t-tests. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Normal Distribution
CDF and PDF for normal distributions. Step-by-step solution with formula, example dataset and interpretation guide.
Binomial Distribution
Binomial probabilities P(X=k). Step-by-step solution with formula, example dataset and interpretation guide.
Poisson Distribution
Poisson event probabilities. Step-by-step solution with formula, example dataset and interpretation guide.
Geometric Mean
Geometric mean for rate data. Step-by-step solution with formula, example dataset and interpretation guide.
Harmonic Mean
Harmonic mean for rate and speed data. Step-by-step solution with formula, example dataset and interpretation guide.
Weighted Average
Weighted mean with custom weights. Instant result with formula, examples and step-by-step calculation. Free online calculator.
IQR Calculator
IQR, quartiles and outlier detection. Step-by-step solution with formula, example dataset and interpretation guide.
Linear Regression
Slope and intercept of regression line. Step-by-step solution with formula, example dataset and interpretation guide.
Statistical Power
Power of hypothesis tests. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Trimmed Mean
Trimmed mean robust to outliers. Step-by-step solution with formula, example dataset and interpretation guide.
Probability Calculator
Event probability and odds. Step-by-step solution with formula, example dataset and interpretation guide.
Cronbach's Alpha
Internal consistency reliability. Full formula with variable legend, worked example and step-by-step chemistry solution.
One-Way ANOVA
Analysis of variance across multiple groups. Step-by-step solution with formula, example dataset and interpretation guide.
Mann-Whitney U Test
Non-parametric comparison of two groups. Instant result with formula, examples and step-by-step calculation. Free online calculator.
F-Test Calculator
Compare variances of two groups. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Type I & II Errors
Understand alpha, beta and power. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Matrix 2×2 Calculator
Determinant, inverse, addition and multiplication of 2×2 matrices. See formula, step-by-step solution and all rearrangements. Instant math solver.
Proportion Calculator
Solve for the missing value in a proportion a/b = c/x. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Set Theory Calculator
Union, intersection, difference and symmetric difference of sets. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Divisibility Rules Checker
Check divisibility by 2–12 with instant rule explanations. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Square Root & Powers Calculator
Square root, cube root, nth root, squares and cubes. Instant result with formula, examples and step-by-step calculation. Free online calculator.
Outlier Calculator
Detect outliers using the IQR method. Instant result with formula, examples and step-by-step calculation. Free online calculator.