Daniel Oh
Featured contributor MSc Applied Statistics; 7 years in analytics and data tooling.

Daniel Oh

Senior Contributor, Math & Statistics

0 calculators 0 articles Member since Jun 2026
Math

Permutations (nPr) Calculator

Compute the number of permutations P(n, r) — the number of ways to arrange r items from n distinct items where order mat...

basic
20,394 4.5 1 min
Math / Geometry

Arc Length Calculator

Compute the arc length of a circle from the radius and the central angle in degrees.

basic
20,219 3.9 1 min
Other / Tech

Password Entropy Calculator

Compute the bits of entropy of a password from the size of the character set drawn from (lowercase, uppercase, digits, s...

basic
19,028 4.4 1 min
tutorial Math

Percentages Without the Headache

Every "X% of Y" problem, every "what percent of", every percent-change question — written out the way you'd actually say them.

Daniel Oh Daniel Oh
3 min