Free
$0no card needed
- The Daily, every day
- 36 practice questions a day, each with an explanation: 12 easy, 12 medium, 12 hard
- Full-length Test A and Challenge Test 1
- All 1,023 vocabulary words: browse, flashcards and quiz
Digital SAT practice
Reach your peak.
A quick run every day, an explanation for every question, and full-length tests on official timing.
Free, no card. You also get 36 practice questions a day: 12 easy, 12 medium and 12 hard.
The DailySTEP 1
- Three hearts. A miss costs one.
- Streaks pay. ×2 from three in a row, ×3 from six.
- Your longest streak. Beat it tomorrow.
Full-length tests
The real test, rehearsed.
98 questions across four modules, in the digital SAT’s order and on its timing, with a highlighter, a question map and a timer you can see.
How it works
One run a day. One skill at a time.
-
1
Play the Daily.
A quick run with three hearts. String right answers together and the questions get harder and the points multiply.
-
2
Miss one, learn why.
Every question is tagged by domain and skill, and every answer comes with an explanation.
-
3
Drill that skill.
Practice any single skill at any difficulty, or just the questions you got wrong.
-
4
Beat your best.
Come back tomorrow and climb. Progress shows your accuracy and your strongest skills.
Built around the real SAT blueprint.
Every question is tagged by section, domain, skill and difficulty, so you can practice exactly what you need. Full tests run like test day: two Reading & Writing modules, a break, then two Math modules.
Free daily practice
12 easy, 12 medium and 12 hard questions free every day, each with a full explanation. Filter by section, domain, skill and difficulty. Resets at midnight.
Real SAT timing
Take any test on official timing, extended 1.5× time, or untimed to focus purely on accuracy.
Adaptive full-length tests
Four modules in official order. The second module of each section adapts to how you did on the first.
Vocabulary
1,023 essential SAT words. Browse the list, flip flashcards, or quiz yourself.
Your progress
Accuracy across daily practice and full tests, your strongest skills, and the ones that need the most help.
Games
PEAK Survivor, Hole and Peak Defense: three games powered by SAT practice questions.
Explanations
Every answer, explained.
Not just the right letter: how to get there, and why the tempting answer is wrong.
MathProblem-Solving and Data AnalysisHard
A store raises the price of a jacket by 20%. Later, it lowers the new price by 20%. The final price is what percent of the original price?
A80%
B96%Correct
C100%The trap
D104%
Check with $100: $100→then$120→then$96
Turn each change into a multiplier.
Up 20% means × 1.20. Down 20% means × 0.80.
Apply them in order.
1.20 × 0.80 = 0.96
Read the answer.
The final price is 96% of the original. That’s B.
Why not 100%?
The 20% cut is taken from the higher price, so it removes more than the 20% increase added.
Test day
What test day looks like.
Every Peakscor full test follows this order. In the standard tests, the second module of each section adapts to how you did on the first.
-
Reading & Writing · Module 1
27 questions32 min
-
Reading & Writing · Module 2
27 questions32 min
Adapts to how you did on Module 1. -
Break
10 min
-
Math · Module 1
22 questions35 min
-
Math · Module 2
22 questions35 min
Adapts to how you did on Module 1.
98 questions · 2 hr 14 min of testing, plus the break
Peakscor by the numbers
- 36free practice questions every day
- 98questions in every full-length test
- 1,023SAT vocabulary words
- 1.5×extended-time option on every test
Plans
Free every day. Pro when you’re serious.
The free plan is the real thing, not a trial. Pro removes the limits. Peak adds the full course and a plan to test day.
Pro
$20a month, or $200 a year
- Everything in Free
- Unlimited practice, no daily limit
- Every full-length test and Challenge test
Peak
$29a month, or $280 a year
- Everything in Pro
- The full Learn course: every lesson and mastery quiz
- Peak Plan, day by day to test day
Prices in US dollars. Cancel anytime.
FAQ
Questions, answered.
The Daily, plus 36 practice questions every day: 12 easy, 12 medium and 12 hard, each with a full explanation. Full-length Test A, Challenge Test 1 and all 1,023 vocabulary words are free too. No card needed.
Pro is $20 a month or $200 a year: unlimited practice with no daily limit, plus every full-length test and Challenge test. Peak is $29 a month or $280 a year: everything in Pro, plus the full Learn course and Peak Plan. Cancel anytime from your account.
98 questions across four modules, in the digital SAT’s order: Reading & Writing Module 1 and Module 2 (27 questions each), a 10-minute break, then Math Module 1 and Module 2 (22 questions each). On official timing that’s 2 hr 14 min of testing. You get estimated section scores and a total at the end.
Yes. In the standard full-length tests, Module 2 of each section is the harder version if you get 60% or more of Module 1 right, and the easier version if you don’t. Challenge tests use the hardest material throughout.
Official timing, extended 1.5× time, or untimed, on every test, including the free ones. Extended time allows 48 minutes for each Reading & Writing module and about 52 for each Math module. Untimed removes the clock so you can focus on accuracy.
A quick run with three hearts. Each right answer builds your streak: the questions get harder as it grows, and your points multiply (×2 from three in a row, ×3 from six). A miss costs a heart and drops you back to easy. Best is your longest streak.
Every day at midnight. You get a fresh 12 easy, 12 medium and 12 hard.
No. Peakscor is an independent SAT practice tool, not affiliated with the College Board. Scores shown are estimates.
Your next point starts today.
Free, no card.
Evaluating statistical claims · Lesson 1
Observational studies and experiments
Every question in this skill describes a study and asks what it can and can't show. Start with one question: who decided which group each person or thing was in?
In an observational study, researchers only record what already happens. They might survey 260 students about whether they eat breakfast and compare their test scores. The students decided for themselves whether to eat breakfast. The researchers didn't.
In an experiment, researchers impose a treatment: they decide who gets it. When they use a chance process, such as a coin flip or a random number generator, to decide who gets which treatment, that is random assignment.
Why it matters: students who eat breakfast may also sleep more, have more support at home or get to school on time. Any of these other differences, called confounding variables, could explain higher scores. Random assignment spreads such differences across the groups by chance, so they tend to balance out. If the treated group then does clearly better, the treatment is the best explanation.
The rule: only random assignment supports a cause-and-effect conclusion. An observational study, however large or careful, can show an association (two things tend to go together), but not that one causes the other.
Two more details. The difference between groups has to be larger than chance alone would produce; a study description may signal this with words such as significantly higher. And which people a conclusion applies to is a separate question, covered in Lessons 2 and 4.
Worked example Easy
A researcher studied 320 adults who work in the same city. Each adult reported whether they ride a bicycle to work, and the researcher measured each adult's resting heart rate. The adults who rode a bicycle to work had a significantly lower average resting heart rate than the adults who did not.
Which statement about this study is true?
- It is an experiment, so it shows that riding a bicycle to work lowers resting heart rate.
- It is an experiment, because the researcher compared two groups of adults.
- It is observational, so it can't show that cycling to work lowers resting heart rate.Answer
- It is an observational study, so it shows that riding a bicycle to work lowers heart rate.
How to solve it
- Ask who decided the groups. Each adult already rode a bicycle to work or didn't; the researcher only recorded it.
- Recording what people already do makes this an observational study, not an experiment.
- Without random assignment, other differences could explain the result. Adults who cycle to work may also exercise more in their free time. So the study shows an association between cycling and lower heart rate, not that cycling causes it.
Why each choice is right or wrong
- A. Incorrect. The researcher didn't assign anyone to ride or not ride; each adult chose. That makes the study observational, and without random assignment it can't show cause.
- B. Incorrect. Comparing groups doesn't make a study an experiment. In an experiment the researcher decides who gets the treatment; here the adults chose for themselves.
- C. Correct. The adults chose how to get to work and the researcher only recorded it, so the study is observational. Cyclists may differ in other ways, such as exercising more, so the lower heart rates show an association, not cause and effect.
- D. Incorrect. The study is observational, but that is exactly why it can't show cause. Other differences between cyclists and non-cyclists could explain the lower heart rates.
Worked example Medium
A gardener has 40 tomato plants of the same variety. She uses a random number generator to assign 20 of the plants to receive a new fertilizer; the other 20 receive no fertilizer. All 40 plants get the same sunlight and water. By the end of the season, the fertilized plants had produced a significantly greater average weight of tomatoes.
Which conclusion is best supported by the study?
- The fertilizer was the likely cause of the greater production among the plants in this study.Answer
- The new fertilizer increases tomato production for every variety of tomato plant.
- Cause can't be concluded, because the plants weren't randomly selected from all tomato plants.
- No conclusion is possible, because a group of 40 plants is too small to study.
How to solve it
- Who decided the groups? The gardener, with a random number generator. That is random assignment, so this is an experiment.
- The difference was significant, and the only planned difference between the groups was the fertilizer. So a cause-and-effect conclusion is supported.
- To whom does it apply? All the plants were one variety and weren't randomly selected from a larger population, so the conclusion is about the plants in this study.
Why each choice is right or wrong
- A. Correct. The plants were randomly assigned to the two groups, so other differences between plants tend to balance out, and the significant difference points to the fertilizer as the cause for these plants.
- B. Incorrect. The study used one variety of tomato, and its plants weren't randomly selected from all tomato plants. The result can't be stretched to every variety.
- C. Incorrect. This mixes up random selection with random assignment. Random selection decides who a result can be applied to; random assignment, which this study used, is what supports cause and effect.
- D. Incorrect. The study reports a significant difference, which means a difference that large would be unlikely to come from chance alone with this many plants. The size of the group doesn't block a conclusion.
Trap Calling any comparison an experiment
A study that compares two groups is not automatically an experiment. If the subjects ended up in their groups by their own choice or circumstances (people who own a car and people who don't, people who live near a park and people who don't), the study is observational, however carefully the groups are measured. Look for who assigned the groups, and how.
Trap Upgrading an association to a cause
Observational results are reported with words such as linked to, associated with or tend to. A choice that turns that into causes, improves, reduces or leads to claims more than the study shows. So does a choice about what would happen if people were made to change their behavior, since that is a claim about cause too.
Desmos When Desmos isn’t faster
Desmos doesn't help with this lesson. Deciding whether a study is an experiment is a reading question, not a calculation, and there is nothing to graph.
Spend the time instead rereading the sentence that says how the groups were formed. Words such as randomly assigned signal an experiment; chose or compared people who already signal an observational study. Words about how data were gathered, such as reported or surveyed, don't settle it on their own: subjects in an experiment can report their results too.
Practice
Choose a section, then practice a whole domain or drill a single skill.
Full-length tests
Each test mirrors the digital SAT: 98 questions across four modules, 2 hr 14 min on official timing.
A little harder than the real SAT. These tests can run slightly tougher than test day, which makes them good practice: if you can handle these, the real one should feel easier. No question appears in more than one test, Challenge Tests included.
Challenge Tests Hardest of the hardest
Same 98-question format, but every question is drawn from the toughest SAT material: Challenging-tier math throughout and the hardest reading.
Vocab
Study the classic SAT vocabulary list. Browse, flip flashcards, or quiz yourself.
Free every day. Pro when you're serious.
Practice free every day. Pro removes the limits. Peak adds the full course and a plan to test day.
FREE
$0forever
- ✓ 12 easy + 12 medium + 12 hard daily
- ✓ Practice by any SAT domain
- ✓ Explanations on every question
- ✓ Test A and Challenge Test 1
- ✓ The first lesson of every Learn module
PRO
$200/ year
About $16.67 a month, save $40
- ✓ Everything in Free
- ✓ Unlimited daily practice
- ✓ Every full-length and Challenge test
- ✓ Every timing mode
Full course and plan
PEAK
$280/ year
About $23.33 a month, save $68
- ✓ Everything in Pro
- ✓ Every Learn lesson, summary and mastery quiz
- ✓ Peak Plan: a day-by-day plan to test day
- ✓ Cancel anytime
Prices in USD. Switch or cancel your plan at any time.