Every time you answer, you also say how sure you were: you know it, you are not sure, or you are guessing. That second answer is the signal. It turns one score into six outcomes, so a lucky guess and real mastery stop looking identical.

Not to practice. You can take a test and see your results without signing up. An account is what saves your history, so the app can build later tests around what you actually missed.

As long as you want. Ten questions is a warm-up, twenty-two is one module, forty-four is a full math section. You pick the length when you create the test.

Yes. The site works on any phone browser, and there is a native iOS app in beta.

Mastery is sure and correct. Misconception is sure and wrong, which is the most dangerous one. Lucky is unsure and correct. Shaky is unsure and wrong. Fluke is a guess that landed. Stumped is no idea or skipped.

Because you will not study it. A guess already feels like a gap. A confident miss feels like a win until the day it costs you points, so it is the outcome the app pushes hardest to surface.

It is one extra tap, and it is the tap that makes the results worth reading. Most students settle into it within a few questions.

Skipping is itself a signal, and it records as Stumped. That is honest, and it is more useful than a forced guess.

SAT and PSAT are live now. ACT, SSAT, HSPT and ISEE are on the way, and clicking one tells us to hurry.

The bank is written and reviewed to match the style, difficulty tiers, and topic frequencies of the real exams. Every question is tagged by topic and by how often that topic actually shows up.

No. Real exam questions are copyrighted. Ours are written to the same specifications, which is what every reputable prep company does.

Questions are graded easy, medium, hard and insane, mapped to the score band a student at that level is working in. You choose the tier, and lower tiers are always included so a test never becomes all-or-nothing.

Yes. The test builder lets you pick topics and difficulty cell by cell, so you can spend a whole session on the two things you keep missing.

Desmos is built into math questions where graphing helps, and it opens prefilled with the question's equations. There is a Bluebook-style reference sheet too.

You get the six-outcome breakdown, a worked solution for every question, and a mastery radar showing which topics are solid. Then the app builds a follow-up test out of everything you did not master.

A per-topic score that only counts answers you were sure about. A lucky guess cannot inflate it, which is the whole point.

A test weighted toward your weak spots rather than picked at random. The weaker a topic, the more of the test it takes up.

Yes, once you have an account. Sign in anywhere and your attempts, radar and progress come with you.

The core is free forever: practice, the signal, results, review, and the mastery radar. Signal Plus adds unlimited AI-tailored tests and full analysis history.

14.99 dollars a month, or 39 dollars for a four-month season pass that does not renew. Both are opening soon.

No. Teachers are free, with no limit and no end date, and a student opening a test from a teacher's link never sees a paywall.

Any time, and you keep Signal Plus until the end of the period you already paid for.

A test composer, printable worksheets with answer keys, a class roster, and a performance matrix that shows the confidence signal per student and per topic.

They can open a shared test from a link. An account is what lets their results roll into your roster over time.

That is the point of the matrix. A quiet seven out of ten built on lucky guesses cannot hide in a percentage.

We store your attempts so the app can teach you. We do not sell them. The full detail is in the privacy policy.

Yes. Email us and we will remove it along with your attempt history.