F1 Passing Score 2026: Exactly What You Need to Pass

How F1 Scoring Actually Works

ASE does not publish a simple "you need 70% correct" number for the F1 Compressed Natural Gas Vehicle exam, and that's the source of most of the confusion candidates bring into their prep. What ASE does confirm is the structure: the initial F1 exam contains 65 multiple-choice questions, but only 55 of those are scored. The remaining 10 are unidentified, unscored research items that ASE uses to evaluate future questions. You won't know which ones are which while you're testing, so every question deserves your full attention.

Because ASE doesn't release a raw percentage cutoff for public consumption, the practical strategy is different from chasing a magic number. Your job is to maximize correct answers across all 55 scored questions, with extra focus on the domains that carry the most weight. That's a more useful mental model than trying to guess an exact passing threshold, and it's the same approach we walk through in the F1 Study Guide 2026.

The 65-Question Format Explained

Understanding the mechanics of the test day experience helps you pace yourself correctly. The initial F1 exam is delivered computer-based at Prometric test centers - this is in-person testing, not remote proctoring. You have 90 minutes to work through all 65 questions (scored and unscored combined), which averages out to roughly 83 seconds per question if you split time evenly. In practice, some questions (especially diagnostic scenarios) take longer, while straightforward recall questions go faster.

The test is closed-book, though an English-to-Spanish glossary is available if you need it. There's no partial credit and no penalty for guessing beyond the lost opportunity to get that item right, so never leave a question blank. If you're unsure how difficult the actual question style tends to be compared to what you've studied, our breakdown at How Hard Is the F1 Exam? Complete Difficulty Guide 2026 covers the reasoning style ASE uses for CNG-specific scenarios.

Domain Weighting and Why It Matters for Your Score

The 55 scored questions are distributed across six content domains, and the distribution is not even. This is the single most important fact for anyone trying to be strategic about passing, because it tells you exactly where your study hours produce the most scoring return.

Notice that Domains 4 and 5 together account for nearly half of the scored questions - 27 out of 55. If your study time is spread evenly across all six domains instead of weighted toward these two, you're leaving points on the table. For a full walkthrough of each domain's task list and typical question angles, see the F1 Exam Domains 2026: Complete Guide to All 6 Content Areas.

What Counts Toward Your Score (and What Doesn't)

A few mechanical details affect how your effort translates into a passing outcome:

• Only 55 of 65 questions are scored. The other 10 research items don't count for or against you, but you can't identify them, so answer every question as if it counts.
• No partial credit exists for multiple-choice items - each question is right or wrong.
• Time management matters indirectly. Running out of time before answering all 65 questions means unanswered scored questions count as incorrect.
• Scope matters. Both dedicated and bi-fuel CNG vehicle configurations are in scope across all six domains, so don't study one configuration type and skip the other.

If you want a condensed, single-page reference of the facts that matter most on test day, bookmark the F1 Cheat Sheet 2026: One-Page Review of Must-Know Facts alongside your primary study materials.

If You Don't Pass: Retake Rules and Timing

ASE builds specific waiting periods and expiration windows into the F1 testing process, and understanding them now prevents wasted money later.

• 30-day wait after a failed attempt. You must wait 30 full days before you can purchase and schedule the same F1 test again.
• 90-day completion window. Once you purchase a test, you must complete it within 90 days or the registration lapses.
• Cost adds up on retakes. The 2026 fee structure is $62 per test plus a $34 registration fee per order, for $96 total before tax on a single test purchase - a cost worth avoiding twice by preparing thoroughly the first time. Full pricing mechanics, including how the registration fee applies across multiple tests in one order, are covered in the F1 Certification Cost 2026: Complete Pricing Breakdown.

F1R Recertification Scoring Differences

If you're renewing an existing F1 credential rather than testing for the first time, the exam experience - and by extension the scoring dynamics - is meaningfully shorter. F1 certification lasts 5 years, and the F1R recertification exam has only 28 questions with no additional unscored research items and a 45-minute time limit. That's less than half the question count and half the time of the initial exam.

Another key difference: eligible recertification candidates may test remotely through Prometric ProProctor, while the initial F1 exam requires in-person testing at a Prometric test center. This flexibility doesn't change how the content is weighted, but it does mean recertification prep can be lighter and more targeted toward refreshing domain knowledge rather than building it from scratch.

Aligning Study Time With Scored Question Counts

Since Domain 5 alone accounts for roughly 16 of 55 scored questions and Domain 4 another 11, a study plan that mirrors this weighting will outperform one that treats all domains equally. A simple way to structure a multi-week plan is to allocate study sessions in rough proportion to each domain's scored question count, front-loading the two heaviest domains early so you have time to revisit weak spots before test day.

This is a study-time allocation strategy, not a generic productivity system - it works because it's tied directly to how ASE weights the F1 exam's scored questions. For a broader look at pacing an entire prep timeline around your test date, the F1 Study Guide 2026: How to Pass on Your First Attempt expands on weekly structuring in more depth.

Running timed practice tests that mirror the 65-question, 90-minute format is one of the most reliable ways to find out whether your pacing and domain knowledge actually hold up under exam conditions, rather than just under open-book review.

FAQ

Understanding exactly how the F1 exam is scored - 55 scored questions, six weighted domains, and firm retake timing - turns a vague "study everything" plan into a focused one. Pair that structural knowledge with realistic practice under timed conditions, and you'll walk into test day knowing precisely where your effort has gone and why it should pay off.