Statistical Tables · free & public domain

Pearson Correlation Critical Values (PPMC)

Critical values of Pearson’s r by sample size, for testing H₀: ρ = 0.

How to use this table

Read down to your sample size n, across to your two-tailed α. Reject H₀: ρ = 0 — that is, call the correlation significant — if |r| exceeds the value. Example: n = 20 at α = 0.05 → 0.444, so an observed r of 0.52 is significant but 0.41 is not. Indexed by n directly, so there is no d.f. conversion to get wrong.

The table

Pearson Correlation Critical Values (PPMC)
n / two-tail α0.10.050.020.010.001
30.9880.9971.0001.0001.000
40.9000.9500.9800.9900.999
50.8050.8780.9340.9590.991
60.7290.8110.8820.9170.974
70.6690.7540.8330.8750.951
80.6210.7070.7890.8340.925
90.5820.6660.7500.7980.898
100.5490.6320.7150.7650.872
110.5210.6020.6850.7350.847
120.4970.5760.6580.7080.823
130.4760.5530.6340.6840.801
140.4580.5320.6120.6610.780
150.4410.5140.5920.6410.760
160.4260.4970.5740.6230.742
170.4120.4820.5580.6060.725
180.4000.4680.5430.5900.708
190.3890.4560.5290.5750.693
200.3780.4440.5160.5610.679
210.3690.4330.5030.5490.665
220.3600.4230.4920.5370.652
230.3520.4130.4820.5260.640
240.3440.4040.4720.5150.629
250.3370.3960.4620.5050.618
260.3300.3880.4530.4960.607
270.3230.3810.4450.4870.597
280.3170.3740.4370.4790.588
290.3110.3670.4300.4710.579
300.3060.3610.4230.4630.570
320.2960.3490.4090.4490.554
340.2870.3390.3970.4360.539
360.2790.3290.3860.4240.525
380.2710.3200.3760.4130.513
400.2640.3120.3670.4030.501
450.2480.2940.3460.3800.474
500.2350.2790.3280.3610.451
600.2140.2540.3000.3300.414
700.1980.2350.2780.3060.385
800.1850.2200.2600.2860.361
900.1740.2070.2450.2700.341
1000.1650.1970.2320.2560.324
1500.1350.1600.1900.2100.266
2000.1170.1390.1640.1820.231

Indexed by sample size n (not d.f.), with a 0.001 column and n to 200.

How these values were produced

r = t/√(t² + d.f.) with d.f. = n − 2 — the exact equivalence between the t test and the correlation test (SciPy 1.17).

Every one of these 210 values was computed from the underlying distribution — none was transcribed from a printed table. Values of this kind are mathematical facts: they come out the same for anyone who computes them correctly.

Need the test run rather than the critical value looked up? The Proof Workbench computes t, r, χ² and ANOVA in your browser with assumption checks and a re-verifiable receipt.

Use it freely

This table is dedicated to the public domain under CC0 1.0. No attribution required, no signup, no limits — copy it into a lecture, a textbook, or your own site. A link back is welcome but not asked for.

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