Certification Exam Difficulty: How to Compare Different Exams

Ask five people whether the Certified Information Systems Security Professional (CISSP) exam is harder than the Offensive Security Certified Professional (OSCP) exam and you will get five confident answers — none of them comparable, because each person is measuring something different. One remembers time pressure, another remembers the experience it took to qualify, a third remembers a 24-hour practical ordeal. Difficulty is not one number. It is at least four separate properties, and you can only compare two exams honestly by scoring them on each property separately.

This article gives you that framework and shows it in action on real exam pairs. It deliberately does not rank the hardest exams — if that is what you came for, the rankings of the hardest IT certification exams and the hardest cloud certification exams cover that ground.

Why "which exam is harder?" is usually the wrong question

Difficulty is relative to the person sitting the exam. A network engineer with eight years of operations experience may find a management-heavy exam like ISACA's Certified Information Security Manager (CISM) harder than a deeply technical one, simply because nothing in their day job rehearses governance vocabulary. A project manager would experience the reverse. So the useful question is not "which exam is harder?" but "which exam is harder for someone with my background, and by how much?"

That reframing matters for planning. If two credentials would serve your career equally well, the rational choice is the one whose difficulty profile overlaps most with what you already do daily — you are borrowing study hours from your own experience.

The four criteria that actually measure exam difficulty

1. Question format: what kind of thinking is being tested?

Format is the single biggest difficulty variable, because different formats fail candidates in different ways.

Linear multiple choice is the baseline: a fixed set of questions, answered in any order, with review allowed. Google's Associate Cloud Engineer exam (50–60 multiple choice and multiple select questions over 2 hours) and the AWS Certified Cloud Practitioner exam (65 questions in 90 minutes) sit here. You can skip, flag and return — recovery from a bad patch is possible.

Adaptive testing removes that safety net. The CISSP exam uses computerised adaptive testing (CAT) in all its exam languages: 100 to 150 items in a maximum of 3 hours, with no going back — the exam adjusts to your performance as you go. An adaptive exam of 100–150 questions can feel more punishing than a linear exam of 180, because every question counts the moment you answer it.

Performance-based and practical formats test doing rather than recognising. CompTIA's Security+ and Network+ exams mix multiple choice with performance-based items inside a 90-minute window. Further along the spectrum, the Certified Kubernetes Administrator (CKA) exam is entirely performance-based: 2 hours at a live command line. At the extreme, Red Hat's RHCSA exam (EX200) puts you in front of real systems with no internet access, and the OSCP exam runs 24 hours against live machines. A candidate who excels at multiple choice may struggle badly here, and vice versa — which is why the EC-Council Certified Ethical Hacker (CEH) knowledge exam (125 multiple-choice questions in 4 hours) and the OSCP should never be called equivalent despite both covering offensive security.

Some exams are notorious specifically for how their questions are written rather than what format they use; that is its own topic, covered in the guide to certification exams with the most challenging questions.

2. Breadth: how much territory does the syllabus cover?

Two exams with identical formats can differ enormously in surface area. Compare exam-outline documents side by side and ask three questions:

1. How many domains, and how disparate are they? CISSP spans eight domains from cryptography to physical security; ISC2's SSCP covers seven but at an operational level. Breadth multiplies revision load because context-switching between domains is itself costly.
2. How deep does each domain go? A foundational exam like Azure Fundamentals (AZ-900, a 45-minute exam) touches many topics lightly. An associate-level exam covers fewer topics but expects working fluency.
3. Does the exam include scenario superstructures? Google's Professional Cloud Architect exam builds 20–30% of its questions on published case studies — an extra layer of preparation that a raw domain list does not reveal.

The practical technique: print both exam guides, highlight every objective you could already teach a colleague, and compare the unhighlighted remainder. That residue, not the total page count, is your personal difficulty.

3. Assumed experience: the invisible prerequisite

Providers publish two very different kinds of experience statement, and confusing them distorts every comparison.

Hard requirements gate the credential itself. CISSP demands five years of cumulative paid experience across two or more of its domains (a degree can waive one year); pass the exam without it and you become an Associate of ISC2, not a CISSP. PMI's Project Management Professional (PMP) certification requires documented project-leadership experience plus 35 hours of training before you may even register.

Soft recommendations gate nothing but predict pain. Cisco says CCNA candidates "often benefit from one or more years of experience"; AWS suggests a year of hands-on work before the Solutions Architect – Associate exam; CompTIA recommends Network+ plus two years of security or sysadmin work before Security+. None of these stop you booking the exam — they tell you how much of the syllabus the average passer had already lived.

When comparing difficulty, treat a soft recommendation as a debt: if you lack the recommended experience, add the hours needed to simulate it (labs, home projects) to your estimate. An exam that is "easy for a sysadmin" is not easy for you if you are not one yet.

4. Pass threshold, scoring scale and time pressure

Published thresholds let you compare how much of the exam you must get right — but only within context:

• CISSP requires 700 out of 1,000 on its CAT scale, and candidates receive only a pass/fail result, never a score.
• CompTIA Security+ requires 750 on a 100–900 scale; Network+ and Linux+ require 720 on the same scale.
• The CKA requires 66%; ITIL 4 Foundation requires 65% (26 of 40 questions in 60 minutes); the Scrum Alliance Certified ScrumMaster test requires 74% (37 of 50).
• The OSCP requires 70 of 100 points, earned by compromising machines rather than answering questions.

Raw percentages are not directly comparable across different scales and formats — 66% on a live Kubernetes cluster is a different achievement from 74% on multiple choice — but within similar formats they are a fair signal. Then layer on time pressure: divide minutes by questions. Security+'s 90 minutes for up to 90 questions (including hands-on performance items) is far tighter per item than CEH's 4 hours for 125 multiple-choice questions.

What you cannot use: pass rates

It bears repeating as its own point, because "pass rates certification exams" is one of the most-searched difficulty comparisons and one of the least answerable. AWS, Microsoft, Cisco and ISC2 do not publish pass rates for these exams. Sites that quote "the CISSP pass rate is X%" are guessing. A responsible difficulty comparison uses formats, thresholds, experience gates and time pressure — all published — and leaves pass rates out.