Square root
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Click here or press Esc to resumeSquare Drill is a recall trainer for the small set of numbers worth learning by heart: the squares up to 50, the cubes up to 15, and the powers of 2. It is not a calculator and not a lesson — it assumes you can already work these out, and trains you to recall them instantly.
That distinction matters more than it sounds. In a timed paper, a fact you can derive in eight seconds and a fact you simply know are not the same fact. The first one costs you the thread of whatever you were actually solving. Most of the value of drilling here is protecting your attention for the harder step that comes after.
They turn up constantly once you are past basic arithmetic — recognising 361 as
19² when factorising, spotting that 1024 is 2¹⁰ in a
counting problem, or noticing a Pythagorean triple because 169 is familiar rather than because
you computed it. Competition papers in particular reward recognition over calculation.
13² = 169 and 14² = 196 use the same
three digits in a different order, which makes them easy to swap under time pressure.10³, then a cliff —
13³ = 2197 is a common blank.The drill weights what it asks you. Anything you get wrong returns much more often, items you have not seen yet are shown sooner, and the same question will not repeat immediately. So the session bends itself toward whatever you are worst at rather than spreading effort evenly. Show weak spots makes that visible: what you miss most, and what you are slowest on even when you get it right. Slow-but-correct is usually the more useful signal, because it is the thing that quietly costs you time in an exam.
Everything stays in your browser for the length of the session. There are no accounts, no tracking, and no analytics; your answers and times are never sent anywhere and are gone when you close the tab. The only thing stored between visits is a note that you have already seen the instructions.
Practise squares, cubes and powers of 2 until you learn them. The clock stops while this is open.
Questions you miss come back more often, and ones you have not seen yet come up sooner. Show weak spots lists what you get wrong most and what takes you longest.
Your scores stay in this tab. Close it and they are gone — nothing is saved about you or sent anywhere.