A TI-84 Mock style calculator covering the normal, Student's t, χ², and binomial distributions. Pick a function from the DISTR menu on the screen, then enter your values. Reference tables are below.
z* = 1.645 → 90% CI · 1.960 → 95% · 2.576 → 99%
Use -1E99 / 1E99 (or -999 / 999) for ±∞ in cdf bounds.
χ² and t shapes depend on degrees of freedom (df); as df→∞ both approach the normal/Z curve.
Interactive critical-value and probability tables, computed live. Use the lookup tools to highlight any value, or scan the grids directly.
Reading the table: the body gives the cumulative area P(Z < z) — the area to the left. Row = z to the tenths, column = the hundredths digit. For a right-tail area use 1 − value.
Reading the table: the body gives the critical value t* with the listed area in one tail. The top header row shows the matching two-tail confidence level C. The bottom row (df = ∞) equals the z critical values.
Reading the table: the body gives the critical value χ²* with the listed area to the right. Used for goodness-of-fit, independence, and variance tests.