Bluebook vs Sigma Prep practice tests: take Bluebook first. It has 8 free official tests with real College Board scoring, and nothing else matches that. Sigma Prep has 24 Math tests that mirror those official tests question for question with fresh problems, each in three versions, with a video on every question. Sigma Prep is what you use once the Bluebook tests are gone or when you need to retest without remembering the answers.
We build Sigma Prep. This page says plainly where Bluebook is better, because it is.
Side by side, as of September 2026
| Bluebook | Sigma Prep tests | |
|---|---|---|
| Price | Free | First test free; all 24 with the $49 per month subscription |
| Tests | 8 full-length, whole SAT | 24 full-length Math tests: 8 official mirrors, 3 versions each |
| Scoring | Official, College Board's own algorithm | Estimated 200 to 800 range from the mirrored test |
| Questions | Official questions | Our own variations of the official questions, same skill, same position, new numbers |
| Format | Two-module adaptive, both sections | Two-module adaptive, Math only for now (Reading and Writing is in the works), both second modules built |
| Explanations | Answer key and short rationales | A video on every question |
| Retakes | Same questions again | A fresh version of the same test |
| After the test | Score report | Score estimate, breakdown by domain, and a practice set built from your misses |
Where Bluebook wins
Everything about measurement. The questions are real, the scoring is real, and the interface is the one you will see on test day. A Bluebook score is the number to trust.
Where Sigma Prep wins
Everything after the score. The video on each question, the miss list by topic, the practice set built from it, and a fresh version of the same test to confirm the fix. And volume: 24 tests to Bluebook's 8, on the Math section.
The order that works
- Bluebook test for a real baseline.
- Sigma Prep practice on the topics that cost you points, from Easy to Hard, with the video on every miss.
- Sigma Prep Test 4, the free one, to see whether the gap closed, then a fresh version when you are ready.
- Save two or three Bluebook tests for the last weeks before your date, when you want the official number.
What Sigma Prep tests do not do
They do not give an official score, they do not cover Reading and Writing yet (it is in the works, not available at the moment), and they are not College Board questions. That last one is on purpose: the originals stay clean so your Bluebook sittings keep measuring you.
Try the free diagnostic, twelve real SAT Math questions, no card, or take the free full-length practice test with a free account.