The chi-square calculator computes the χ2 parameters for an table of data.
INSTRUCTIONS: Enter the following:
chi-square (χ2): The calculator returns:
- (DF) Degrees of Freedom
- (χ2) chi-square value
- (Σc) Column Sums
- (Σr) Row Sums
- (ΣOB) Total Sum
How to Enter Data
Click on the text field for parameter OB. You can either upload a CSV file or manually enter rows of data where each observation is separated by a comma as follows:
17,47
22,38
41,58
Chi-square Calculators:
The Math / Science
`"Expected Result" = ("Column Total" * "Row Total")/"Sample Size"`
`χ2 = sum(O^2/E) - sum(O)`
`"Degrees of Freedom" = (R-1)*(C-1)` if R≠1, then DF = C-1
Critical Values

- Observational Stats: This function accepts a table of numbers separated by commas and calculates observational statistics for any of the columns. This includes count, min, max, sum, sum of squares (Σx²), square of the sum (Σx)², mean, median, mode, range, mid point, rand, sort up, sort down, rand, population variance, population standard deviation, the sample/experimental variance, sample/experimental standard deviation.
- Frequency Distribution: This function lets you enter a string of numbers separated by commas, a low and high range and a number of bins. It then computes how many of the observations are in each of the bins between the high and low values designated.
- Paired Sample t-test: This computes the various parameters associated with the Paired Sample t-test.
- ANOVA (one way): The is one way analysis of variance
- (χ2) Chi-Square Test: This computes the Chi-Square value for an nxm array of data and provides the degrees of freedom.
- Linear Regression: This computes the regression line (least-squares) through a set of X and Y observations. It also computes the regression coefficient (r).
- y = a + bx: This is linear equation used with Linear Regression to predict values of Y.
- Wilcoxon Signed Rank Test: This provides the Wilcoxon statistics and critical value for two groups of numeric observations based on an alpha value and whether it's a one or two tailed test.
- Slope-Intercept form of a Line based on two points.
- Slope between two points
- Range value based on the slope-intercept formula of a line and a value of the domain.
- Compute the Probability between z SCORES
- College Level Statistics Calculator (Stat Calc).
- Count of Observations in a Set - this is the number (n) of values in a set.
- Minimum Value in a Set - this is the minimum observed value
- Maximum Value in a Set- this is the maximum value in the set.
- Numeric Sort (up and down) - this returns a comma separated list of the observations in ascending or descending order.
- Create a random subset of the a list of numeric values
- Random number from a range you specify
- Frequency distribution of data.
- Σx - this is the sum of the values in a set.
- Σx² - this is the sum of the squared values
- (Σx)² - this is the square of the summed values.
- Mean - the is the mean (average) of the observed values
- Median - the middle ordered value
- Mode - the most recurring observation
- Mid Point in a Set - this is the mid point of the observation range.
- Range in a Set - this is the difference between the max and the min.
- Population Variance of the values
- Population standard deviation of the values
- Sample Variance of the values
- Sample Standard Deviation of the values
- Compute the z SCORE based on the mean and standard deviation
- Compute the z SCORE in a set of observations
- Compute the percentile of a single observation (y) in a set (X)
- SDOM - standard deviation of mean
- Percent Relative Standard Deviation
The Psychology and Statistics Calculator contains useful tools for Psychology Students. The psychology statistics functions include the following:
- Wilcoxon Signed Rank Test: Enter two sets, whether it's a one or two tail test and an alpha value to see the Wilcoxon statistic and the critical value.
- Bayes' Theorem for Disease Testing: Enter a base rate probability, probability of false positives and the probability of correct positives to see a ratio of people with the disease, approximate number of false and true positives and the theorem's percent likelihood of a having the disease if tested positive.
- chi-square Test: Enter a 3x2 matrix to see the expected values matrix with row and column totals, degrees of freedom and the chi-square value.
- Rescorla-Wagner Formula (alpha and beta version): Enter salience for conditional stimuli, rate of unconditional stimuli, maximum conditioning for unconditioned stimuli and the total associative strength of all stimuli present to see the change in strength between conditional and unconditional stimuli.
- Rescorla-Wagner Formula (k version): Enter Maximum conditioning possible for the unconditioned stimuli, total associative strength of all stimuli present, combined salience of the conditioned and unconditioned stimuli, and number of trials to see the change in strength associated with the trials.
- Ricco's Law: Enter the area of visually unresolved target and constant of background luminance when eyes are adapted to see Ricco's Law factor.
- Ricco's Law (K variable): Enter the scotopic vision constant, background luminance and photopic vision constant.
- Stevens' Power Law: Enter proportionality constant, magnitude of stimulation, type of stimulation exponent to see magnitude of sensation.
- Weber Fraction: Enter just-noticeable difference for intensity and stimulus intensity to see the weber fraction.
- Weber-Fechner's Law: Enter just-noticeable difference for intensity, instantaneous stimulus, stimulus intensity and the threshold to see the factor.
- Random Integer: This provides a random number (integer) between a lower and upper bound.
- Observational Statistics (aka Simple Stats): Observational statistics on a set including: count, min, max, mean, median, mode, mid-point, range, population and sample variance and standard deviation, mean absolute deviation, standard deviation of mean, sum of values, sum of squared values, square of the sum, and the sorted set.
- Frequency Distribution: Frequency distribution of a set of observations in uniformly sized bins between a minimum and maximum.
- Least-squares Trend Line (aka Linear Regression): Linear regression line on a set of paired numbers and see (r) the correlation coefficient,(n) number of observations, (μX) mean of the X values, (μY) mean of Y values, (ΣX) sum of the X values, (ΣY) sum of the Y values, (Σ(X⋅Y) ) sum of the X*Y product values, (ΣX2) sum of X2 values, (ΣY2) sum of Y2 values, (a) y intercept of regression line, and (b) slope of regression line.
- Single-Sample t-test: t-Test parameters including alpha level, population mean and whether it's one or two tailed and see the degrees of freedom, critical t-value, t score and the standard error.
- Paired Sample t-test: Test of two sets of values with an alpha level and whether it's one or two tailed and see the number of observations, mean and standard deviation for both sets, the degrees of freedom, critical t-value, t-score and the Standard Error value.
- Effect Size (r-squared): Enter a t-test result and the degrees of freedom to see r2.
- Effect Size (Cohen's d): Enter the mean from two groups and the estimated standard deviation to see the effective size.
- Analysis of Variance (one way): ANOVA for numeric observations of three groups. Computes the F Score, Numerator: degrees of freedom Between, Denominator: degrees of freedom Within, mean of each group, grand mean, total sum of squares, sum of square within and between, and variance within and between.