About IQ Test Coach
IQ Test Coach is a free, honest online IQ test with full explanations — built by the team behind the IQ Test Pro app.
Why we built it
Most online IQ tests ask for payment after you've answered every question, or give everyone a flattering score. We wanted the opposite: a free score, real scoring, and explanations that help you get better.
How the questions are made
The question bank covers fifteen classic types of reasoning questions. Every question has one correct answer, a hint and a step-by-step explanation, and a difficulty level calibrated from players' answers.
Figure questions are drawn by the app, so they work the same in every language. Word and maths problems are available in English and Vietnamese.
How scores are calculated
We use item response theory (the Rasch model): each question has a difficulty, and your ability is the value that best explains your pattern of answers. Hard questions count for more than easy ones.
Ability is converted to the usual IQ scale (average 100, standard deviation 15). The 90% range comes from the statistical precision of your answers. The adaptive test picks each question to make that range as narrow as possible.
Limits
An online test can't replace a professional assessment by a psychologist. Results depend on your conditions — tiredness, distractions, the device — and the scale is an estimate. Please don't use them for clinical, educational or employment decisions.