Comparing fractions without a single rule

Ask a class whether 1/4 or 1/8 is bigger and many will say 1/8 — because 8 is bigger than 4. That's whole-number bias in its purest form, and the usual fix (cross-multiply, or "bigger bottom means smaller piece") just swaps one memorized rule for another without building any sense of size. This tool never states a rule. It puts both fractions on a shared number line, or as aligned strips starting from the same edge, and lets the class SEE which is longer — which is closer to a whole. The comparison presets deliberately target the exact patterns where bias shows up: same numerator (1/4 vs 1/8), same denominator, and benchmark comparisons around one-half (Ni & Zhou; Braithwaite & Siegler). Comparing by magnitude on a number line is the single most evidence-backed fraction activity there is. The question is always the same: which is closer to a whole, and how do you know — without any rule?