Caltech ACT: Average Scores, Ranges, and What You Need to Know

With a median composite ACT score of 36 and a middle 50% range of 35 to 36, Caltech represents one of the most selective institutions in the country. The fact that the vast majority of admitted students achieve a perfect 36 reflects just how competitive the ACT landscape is at this institution, making it extremely difficult to stand out academically through test scores alone. Many applicants submit perfect scores, which means your standardized test performance must be exceptional simply to be considered in the first place. An institution with a 2.6% acceptance rate accepts only around three out of every one hundred students who apply, and these numbers underscore why strong ACT performance is table stakes rather than a pathway to admission.

A good ACT score for Caltech typically means achieving a 35 or 36, with 36 being the gold standard that puts you at the median among admitted students. However, it is absolutely critical that you understand a high ACT score does not secure your admission to Caltech. Countless applicants with perfect or near-perfect scores are rejected each year because Caltech evaluates you as a complete person, not merely as a test taker. Your high school course rigor, grades, essays, letters of recommendation, research experience, demonstrated interest, and extracurricular activities all play significant roles in the admissions decision. A 36 ACT tells Caltech you have the intellectual capability to survive their demanding curriculum, but it does not tell them whether you should have one of their extremely limited spots.

While Caltech has no official minimum ACT score requirement, you should realistically aim for at least a 35 to have any genuine chance of being considered. Scoring below 35 places you well below the middle 50% range and makes admission significantly more unlikely unless you have extraordinarily compelling qualities elsewhere in your application. Caltech's official admissions materials indicate that scoring below a 33 on individual sections shows a more sizable difference in student performance at Caltech, so any composite score substantially below 35 would put you at a considerable disadvantage. That said, Caltech emphasizes a holistic review process, and if your ACT falls short of their typical range but you have remarkable achievements, demonstrated mastery of STEM concepts through other means, or an inspiring personal narrative, do not rule out applying entirely. Just be realistic about the odds if your score is notably below their range.

Caltech requires all first-year applicants to submit either an SAT or an ACT score as part of their application. The school reinstituted this requirement beginning with the fall 2025 admissions cycle after a period of test-optional admissions. Unlike some schools, Caltech does not require you to submit the ACT writing or science subscores for fall 2026 applicants. The school emphasizes that there is no preferred exam, and they treat the ACT and SAT equally. If you face genuine hardship in accessing testing, Caltech provides an opportunity to explain your circumstances in your application and allows you to demonstrate STEM preparedness through alternative means, but the default expectation is that you submit one of these standardized tests.

Caltech employs a superscoring method for the ACT that benefits you if you test multiple times. If you take the ACT more than once, Caltech considers your highest individual section scores across all test dates and pieces together the strongest possible composite score to review. This means if you score lower on the Math section in one sitting but higher on English in another sitting, Caltech will combine your best results from each section. The Science section is optional, giving you additional flexibility. When you apply, you submit all of your official test scores, and Caltech creates a superscore from that information. This approach gives you more breathing room to take the test multiple times and improve incrementally.

Caltech evaluates your ACT score as just one component within its holistic admissions process, not as the primary driver of your acceptance. The school has explicitly stated that standardized test scores are used alongside high school grades, course rigor, and a comprehensive review of your background and personal situation. Caltech's admissions committee recognizes that standardized test performance, while important for confirming your readiness for rigorous academics, does not define who you are as a student or as a person. The school actually publishes research showing that there was only a small difference in college grades between students who scored 35-36 and 33-34 on the ACT, which indicates that beyond a certain threshold, other factors become the true differentiators. Your application needs to convince admissions officers that you will thrive intellectually, contribute meaningfully to Caltech's tight-knit community, and pursue your intellectual passions with genuine curiosity.

At Caltech's extraordinarily competitive acceptance rate, even an ACT score of 36 does not separate you from thousands of other high-scoring applicants applying for fewer than 350 first-year spots. The admissions committee instead focuses on what makes you distinctive as a researcher, thinker, and community member. Your perfect ACT score demonstrates that you possess the intellectual capability to succeed at Caltech, but the rest of your application demonstrates whether you deserve one of the exceptionally rare admission offers the school extends each year. Caltech looks for students who have demonstrated sustained engagement in STEM, intellectual curiosity that goes beyond the classroom, the ability to think creatively and independently, and the capacity to contribute to a collaborative learning environment. This is why a student with a 35 ACT and groundbreaking research experience sometimes gains admission while a student with a 36 ACT but less compelling overall profile is rejected.

AdmitStudio users who have found success at top colleges often approach their applications as a single, cohesive story, not a checklist of impressive achievements. Rather than treating essays, activities, and recommendations as separate pieces, they focus on presenting themselves as a clear, memorable individual with defined values, motivations, and strengths. Their essays help admissions officers understand why they pursued certain activities, how their experiences shaped them, and what kind of person they would be on campus. This clarity makes it easier for readers to grasp who the applicant is within just a few minutes of review.

AdmitStudio users who are successful also tend to use their essays to connect and reinforce the rest of their application, not repeat it. The essay highlights a few core traits, such as curiosity, leadership, resilience, or initiative, while the activities list and recommendations quietly support those same traits with evidence. By aligning every part of the application around a consistent narrative, these students stand out not because they try to be extraordinary, but because they are specific, authentic, and intentional. Admissions officers come away with a strong sense of the applicant's identity and how they would uniquely contribute to the university community.