# What is Smoke Testing? *Learn what smoke testing is, how teams use it after deployments, common smoke testing examples, and how smoke testing differs from regression testing.* --- **Author:** [Karan Tekwani](https://testowl.ai/author/karan-tekwani) **Read Time:** 3 min read **Published:** May 13, 2026 **Last updated:** September 30, 2026 --- ![What is Smoke Testing?](https://testowl.ai/images/what-is-smoke-testing.webp) :::lead Smoke testing is a quick set of checks that verifies whether the most important parts of an application still work after a new build or deployment. ::: Smoke testing helps teams catch major issues early before deeper testing begins. Instead of validating every feature, smoke tests focus on critical workflows like login, navigation, payments, APIs, or app startup. Most teams run smoke tests immediately after a deployment, code merge, or new release candidate. If smoke tests fail, there’s usually no point continuing with deeper QA because the build itself may be unstable. ## Smoke Testing Explained The term “smoke testing” originally came from hardware testing. Engineers would power on a device and check whether smoke appeared. If smoke came out, something was obviously broken. In software testing, the idea is similar. A smoke test checks whether the application is stable enough for further testing. It’s not meant to find every bug. It’s meant to answer one question quickly: **“Is this build usable enough to continue testing?”** Smoke testing usually covers: - Application startup - User login - Core navigation - Database connectivity - API availability - Critical business workflows For example, after deploying a new e-commerce release, a smoke test might verify: 1. The homepage loads 2. Users can sign in 3. Products appear correctly 4. Cart functionality works 5. Checkout opens successfully If any of those fail, the deployment likely has a major issue. :::callout{title="Smoke testing definition" icon="🧪"} Smoke testing is a lightweight testing process that verifies whether the core functionality of an application works after a new build, deployment, or major change. ::: A lot of teams automate smoke tests because they need fast feedback in CI/CD pipelines. Smoke suites are usually small and designed to finish within a few minutes. ## Why Smoke Testing Matters in Software Testing Without smoke testing, teams often waste time testing unstable builds. Imagine a QA team starts full regression testing on a release where login is already broken. Hours can be lost before someone realizes the build itself should never have moved forward. Smoke testing prevents that situation. It acts as an early quality gate before larger testing cycles begin. ### What smoke testing helps teams avoid - Testing broken deployments - Wasting manual QA effort - Running expensive test suites unnecessarily - Shipping builds with critical failures - Delayed feedback during CI/CD ### Why teams automate smoke tests Automated smoke testing becomes especially useful when deployments happen frequently. Modern engineering teams may deploy: - Multiple times per day - After every pull request - During nightly builds - Across multiple environments Manual verification doesn’t scale well in those situations. That’s why smoke tests are commonly included in broader [test automation guides](/guide/test-automation) and CI/CD workflows. :::highlight Smoke testing is less about deep validation and more about fast confidence that the application is still operational. ::: ## How Smoke Testing Works: A Real Example Suppose a team deploys a new version of a SaaS dashboard application. Before QA begins full testing, an automated smoke suite runs immediately after deployment. ### The smoke test checks: | Area | Validation | | --- | --- | | Authentication | Users can log in | | Dashboard | Main dashboard loads | | APIs | Core APIs return successful responses | | Navigation | Important pages open correctly | | Billing | Subscription page loads | | Database | Application reads data successfully | The smoke suite finishes in about three minutes. ### Scenario 1: Smoke tests pass If all tests pass: - QA continues deeper testing - The build moves further in the pipeline - Teams gain confidence quickly ### Scenario 2: Smoke tests fail If login suddenly fails after deployment: - The pipeline stops - Developers investigate immediately - Regression testing does not continue This is one reason smoke testing reduces wasted testing effort in fast-moving teams. ## Common Smoke Testing Examples Smoke testing examples usually focus on the most important user flows. ### Web application smoke tests - User login works - Homepage loads - Navigation menu opens - Forms submit successfully - Core APIs respond correctly ### Mobile app smoke tests - App launches successfully - User authentication works - Main screens render correctly - Push notifications initialize - Network requests succeed ### API smoke tests - Health endpoints respond - Authentication tokens generate correctly - Important endpoints return valid responses - Database connections work Most smoke test suites stay intentionally small. Large smoke suites eventually become slow and harder to maintain. ## Smoke Testing vs Regression Testing Smoke testing and [regression testing explained for QA teams](/glossary/what-is-regression-testing) are often confused, but they solve different problems. | Smoke Testing | Regression Testing | | --- | --- | | Verifies build stability | Verifies existing functionality still works | | Small test scope | Large test scope | | Runs quickly | Usually takes longer | | Focuses on critical workflows | Covers broader application behavior | | Acts as an early gate | Validates release quality deeply | Smoke testing answers: **“Can we continue testing this build?”** Regression testing answers: **“Did recent changes break existing functionality?”** In practice, smoke testing usually runs before regression testing. ## When Teams Usually Run Smoke Tests Teams commonly run smoke tests: - After deployments - After new builds - Before regression testing - Before staging releases - After infrastructure changes - Inside CI/CD pipelines In mature engineering environments, smoke tests are often fully automated and triggered automatically after every deployment. This becomes even more important as applications grow and test suites become larger. ## Common Problems With Smoke Testing Smoke testing is simple in theory, but teams still run into problems. ### Smoke suites become too large A smoke suite should stay fast. If teams keep adding more tests over time, the suite slowly turns into a partial regression suite and loses its purpose. ### Unstable smoke tests create deployment noise Flaky smoke tests are especially dangerous because they can block deployments incorrectly. Teams dealing with unstable automation often also struggle with [what flaky tests are in automation](/glossary/what-are-flaky-tests). ### Teams test low-priority functionality Smoke tests should validate critical business flows first. Testing minor UI details inside smoke suites usually slows feedback without improving confidence. :::callout{title="Practical advice" icon="⚙️"} A good smoke suite is small, reliable, and focused on the workflows that would stop users from using the product entirely. ::: ## Learn More About Smoke Testing Smoke testing is usually one layer inside a broader quality strategy. To understand how teams combine smoke testing with automation, CI pipelines, and larger testing workflows, these resources help next: - [What is regression testing](/glossary/what-is-regression-testing) - [What is end-to-end testing](/glossary/what-is-end-to-end-testing) - [Complete guide to test automation](/guide/test-automation) - [How to build a practical test automation strategy](/playbook/how-to-build-test-automation-strategy) ## Frequently Asked Questions :::faq ### Is smoke testing manual or automated? Smoke testing can be either manual or automated. Most modern teams automate smoke tests because they need fast feedback after deployments and code merges. ### How long should smoke tests take? Smoke tests are usually designed to finish within a few minutes. If the suite becomes too large or slow, it often starts behaving more like regression testing. ### What is the difference between sanity testing and smoke testing? Smoke testing checks whether the build is stable enough for further testing. Sanity testing usually verifies a smaller set of specific changes or bug fixes. ### Is smoke testing part of regression testing? Not exactly. Smoke testing is usually a smaller, faster validation step that runs before regression testing begins. ### What happens if smoke tests fail? If smoke tests fail, teams typically stop deeper testing and investigate immediately because the build may not be stable enough for further validation. ::: ## Key Figures - DORA identifies five software delivery performance metrics, which evolved from its original four keys ([DORA](https://dora.dev/guides/dora-metrics/)). - A 2002 study prepared for NIST estimated the annual US cost of an inadequate software testing infrastructure at $59.5 billion, and the reduction available from feasible improvements at $22.2 billion ([NIST/RTI, May 2002](https://www.nist.gov/system/files/documents/director/planning/report02-3.pdf)). - Google suggests, as a first guess, a 70/20/10 split of 70% unit tests, 20% integration tests and 10% end-to-end tests, while cautioning against treating the ratio as a rule ([Google Testing Blog, April 2015](https://testing.googleblog.com/2015/04/just-say-no-to-more-end-to-end-tests.html)). ## Sources and Further Reading - [ISTQB Glossary](https://glossary.istqb.org/) — standard definitions of software testing terms - [Martin Fowler: The Practical Test Pyramid](https://martinfowler.com/articles/practical-test-pyramid.html) — how to balance unit, integration and end-to-end tests - [DORA software delivery metrics](https://dora.dev/guides/dora-metrics/) — deployment frequency, lead time, change failure rate and recovery time ## Related Posts 1. [What is Regression Testing?](https://testowl.ai/glossary/what-is-regression-testing) ![What is Regression Testing?](https://testowl.ai/images/what-is-regression-testing.webp) 2. [Test Automation Guide & Best Practices](https://testowl.ai/guide/test-automation) ![Test Automation Guide & Best Practices](https://testowl.ai/images/test-automation-the-complete-guide.webp) 3. [Test Automation Strategy: A Practical Roadmap](https://testowl.ai/playbook/how-to-build-test-automation-strategy) ![Test Automation Strategy: A Practical Roadmap](https://testowl.ai/images/how-to-build-a-test-automation-strategy-that-scales.webp)