Unit Testing & TDD Test
Tests unit testing and test-driven development — what makes a good unit test, the red-green-refactor cycle, test doubles such as mocks, stubs and fakes, test design and coverage, and keeping test suites fast, reliable and maintainable in CI. Pass to earn Unit Testing & TDD SOA-UTT.
- Intermediate difficulty.Assumes hands-on experience in the role.
- 20 scenario questions
- 20 minutes, timed
- 70% to pass · 90% for distinction
- Free no sign-up needed
- LinkedIn-ready · add it to your profile in one clickSee how ↓
What is the Unit Testing & TDD Test?
The Unit Testing & TDD Test is a free intermediate-level, 20-minute skill test from Science of Apps. It tests unit testing and test-driven development — what makes a good unit test, the red-green-refactor cycle, test doubles such as mocks, stubs and fakes, test design and coverage, and keeping test suites fast, reliable and maintainable in CI. Score 70% or more on its 20 questions to earn a verifiable Unit Testing & TDD certificate (SOA-UTT). Every question is based on published standards and research — including Test Driven Development (Martin Fowler), The Practical Test Pyramid (Martin Fowler), pytest documentation (pytest-dev) — and each answer is explained with its source.
Built for your job title
Software engineer, Test automation engineer, QA engineer, Backend developer and Front-end developer — and anyone who wants quick, verifiable proof of Unit Testing & TDD skills for a CV or LinkedIn.
- Software engineer
- Test automation engineer
- QA engineer
- Backend developer
- Front-end developer
What the test covers
Four skill areas with 5 questions each, drawn from a bank of 10 per area, so a retake brings questions you haven't seen.
- 01
Unit Testing Fundamentals
25%- Good unit tests
- Arrange-Act-Assert
- Test pyramid
- 02
Test-Driven Development
25%- Red-green-refactor
- TDD benefits
- Design feedback
- 03
Test Doubles and Isolation
25%- Mocks, stubs and fakes
- Dependency injection
- Over-mocking
- 04
Coverage, Maintenance and CI
25%- Code coverage
- Test smells
- Continuous integration
Based on published standards
The questions are original scenarios, and each one names the public standard, official guide or research it draws on — shown under the question while you answer, and linked in your review. These are the sources behind this test:
- Test Driven DevelopmentMartin Fowler12 questions
- The Practical Test PyramidMartin Fowler7 questions
- pytest documentationpytest-dev6 questions
- Certified Tester Foundation Level (CTFL) v4.0ISTQB6 questions
- Mocks Aren't StubsMartin Fowler6 questions
- Jest documentationJest (OpenJS Foundation)2 questions
- JUnit 5 User GuideThe JUnit Team1 question
Try a sample question
In test-driven development, the first step of each cycle is to
- write a small failing test for the next bit of behaviour
- write the full production code and then add tests later
- refactor the existing code before any test is written
- run the whole test suite to measure code coverage
Show the answer
A. write a small failing test for the next bit of behaviour — Red, green, refactor. The real test has 20 questions like this.
How the test works
20 minutes, 20 questions
One question per screen, with a progress bar and a countdown. Your progress is saved on this device if you need to pause.
Graded on our server
Answers reach the page only after you submit, so the certificate can only be earned by passing.
Every answer explained
Pass or not, you see every question with the right answer, why, and the source behind it. Pass mark 70%, distinction 90%.
Your certificate
Founder-signed, with a QR code and credential ID. Download PDF or PNG, add to LinkedIn, and it's emailed to you.
What you earn

Pass, then add it to LinkedIn in one click
No typing. The Add to LinkedIn button opens your profile’s Licenses & certifications form already filled in: the certificate name, Science of Apps as the issuer, the issue date, your credential ID and a link recruiters can use to verify it.
- 1Take the 20-minute test
- 2Score 70% or more
- 3Click Add to LinkedIn

Unit Testing & TDD
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Frequently asked questions
What is the Unit Testing & TDD Test?
The Unit Testing & TDD Test is a free intermediate-level, 20-minute skill test from Science of Apps. It tests unit testing and test-driven development — what makes a good unit test, the red-green-refactor cycle, test doubles such as mocks, stubs and fakes, test design and coverage, and keeping test suites fast, reliable and maintainable in CI. Score 70% or more on its 20 questions to earn a verifiable Unit Testing & TDD certificate (SOA-UTT). Every question is based on published standards and research — including Test Driven Development (Martin Fowler), The Practical Test Pyramid (Martin Fowler), pytest documentation (pytest-dev) — and each answer is explained with its source.
How do I take the Unit Testing & TDD Test for free?
Read the four skill areas on this page, then take the 20-minute test online — no fee, course or sign-up. You see every answer explained when you finish. Score 70% or more and you get a Unit Testing & TDD certificate straight away, on screen, as a PDF and by email, with a credential ID anyone can verify.
Are the Unit Testing & TDD Test questions based on real standards?
Yes. The questions are original scenarios written by Science of Apps, and each one is based on a public source you can read: Test Driven Development (Martin Fowler); The Practical Test Pyramid (Martin Fowler); pytest documentation (pytest-dev); Certified Tester Foundation Level (CTFL) v4.0 (ISTQB); Mocks Aren't Stubs (Martin Fowler); Jest documentation (Jest (OpenJS Foundation)). The source is shown under each question and linked in the answer review. Science of Apps doesn't copy questions from other tests.
What does the Unit Testing & TDD Test cover?
Four skill areas with five questions each, drawn from a bank of 10 per area so a retake brings new questions: Unit Testing Fundamentals (Good unit tests, Arrange-Act-Assert and Test pyramid); Test-Driven Development (Red-green-refactor, TDD benefits and Design feedback); Test Doubles and Isolation (Mocks, stubs and fakes, Dependency injection and Over-mocking); Coverage, Maintenance and CI (Code coverage, Test smells and Continuous integration). Every question is an original scenario based on a published standard, official documentation or research, named under the question.
Who should take the Unit Testing & TDD Test?
Software engineer, Test automation engineer, QA engineer, Backend developer and Front-end developer. It suits anyone who wants a quick, verifiable way to show Unit Testing & TDD skills, from students and career switchers to experienced professionals.
Can I use this for unit testing test, test driven development quiz or unit testing interview questions?
Yes. The Unit Testing & TDD Test is free and covers all of these: 20 scenario questions in 20 minutes, each answer explained with the source it comes from, so it works as interview and exam practice. It isn't a full course, so use the areas you miss as your study list. Scoring 70% or more earns a verifiable certificate.
Can I take the Unit Testing & TDD Test from any country?
Yes. The test is online, in English and free everywhere — people take it from India, the US, the UK, Europe, Africa, Latin America and Asia-Pacific. Your certificate is dated with your own local date and can be verified from anywhere at scienceofapps.com/certification/verify/.
How long is the Unit Testing & TDD Test?
20 questions — 5 from each of 4 skill areas — with a 20-minute limit. You need 70% (14 of 20) to pass and 90% for distinction.
How hard is the Unit Testing & TDD Test?
We rate it Intermediate: assumes hands-on experience in the role. It has 20 scenario questions — 5 from each of 4 skill areas — and a 20-minute limit. You need 70% (14 of 20) to pass and 90% for distinction.
How much do Science of Apps certifications cost?
Nothing. There is no fee to take a test, to receive the certificate, to have it emailed or to verify it, and no sign-up.
How are the tests graded?
On our server, not in your browser. The answers never reach the page until you submit, so a certificate can only be earned by passing. Each certificate gets a unique credential ID stored by Science of Apps.
What happens if I don't pass?
You see your score for each area and every question with the correct answer and why, with the published source behind it. You can retake after 30 minutes, and the retake draws questions you haven't seen yet.
Do the certificates expire?
No. Every certificate is dated, so it always shows when you passed. Retake a test any time for a newer date or a higher score.
Can I add the certificate to LinkedIn?
Yes. After you pass, Add to LinkedIn opens the Licenses & certifications form with the certificate name, Science of Apps as the issuer, the issue date, your credential ID and the verification link filled in. You can also download it as a PDF or PNG, and it's emailed to you as a PDF.
How can an employer verify my certificate?
Every certificate has a credential ID and a QR code. Scanning it, or entering the ID at scienceofapps.com/certification/verify/, shows the holder's name, the certification, the score and the issue date from our records.
Are these accredited qualifications?
No. They are Science of Apps' own assessments of applied skill. They aren't issued by a university or standards body, and they work best alongside a portfolio that shows the skills in real work.
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