# What is synthetic monitoring? Synthetic monitoring helps you check whether websites, web applications and APIs are available and performing as expected. It does this by simulating typical user actions to detect technical issues early, often before they affect real users. ## What is synthetic monitoring? Synthetic monitoring is a way to continuously monitor how digital applications behave by **simulating user interactions**. Instead of **relying on real users**, automated scripts run predefined actions at regular intervals. These actions can include opening a web page, filling out a form, logging in or completing a checkout process. The goal is to measure load times, availability and whether individual components are working as they are supposed to. Because the tests repeat the same scenarios at regular intervals, the results can be compared consistently over time. This makes it easier to spot trends, performance changes and recurring issues. Synthetic monitoring is particularly effective for running controlled tests in stable and predefined environments. It allows teams to detect issues at an early stage, often before they impact real users. ## How does synthetic monitoring work? Synthetic monitoring uses **globally distributed checkpoints** or monitoring servers to simulate access from different regions. At set intervals, these servers call up websites, web applications or APIs. During each test, they measure key values such as response time, the load time of individual resources and HTTP status codes. These measurements are carried out independently of real user traffic. From a technical standpoint, the tests are often based on browser emulations or specific HTTP requests. Some tools can also execute JavaScript, which allows them to **replicate specific user interactions**. The collected data is then analysed and displayed in reports or dashboards. If a result exceeds a defined threshold, the system can trigger an alert. This helps teams detect regional issues, network errors, server failures and performance problems early. Synthetic monitoring can also be used to test website speed and to identify ways to optimise your website. Note Modern monitoring strategies often combine synthetic monitoring with AI‑based error analysis. This helps teams detect anomalies automatically and identify possible root causes quickly. Observability also plays an important role by collecting and connecting system data such as logs, metrics, and traces. Synthetic monitoring can also be integrated into [CI/CD workflows](https://www.ionos.co.uk/hosting/ci-cd-workflow "CI/CD workflows: Deploy Now from IONOS"). This allows teams to automate checks on critical user journeys during development and catch performance or availability issues before new updates go live. ## What are the benefits of synthetic monitoring? One of the biggest benefits of synthetic monitoring is that it helps teams detect outages before real users notice them. Because the tests run continuously, availability and performance issues can be identified early. Synthetic monitoring also helps establish a performance baseline. These reference values make it easier to spot gradual slowdowns in load times, which can have a direct impact on sales for an online store. New releases, configuration changes and infrastructure updates can also be checked with predefined tests before they affect users. Synthetic monitoring is also useful for testing APIs that do not have a user interface. It can also test multi-step actions on a website or app, like when a user logs in, searches for a product and completes a payment. If an error occurs, teams can identify exactly which step is affected. Because the tests follow repeatable scenarios, the results are consistent and easy to compare. This makes root cause analysis easier and helps teams resolve issues faster. ## What’s the difference between synthetic monitoring and real user monitoring (RUM)? Synthetic monitoring is not the only way to check how your website performs. With real user monitoring, you can collect data from real visitors while they are using your website. When we compare the two, we see that RUM shows you how your website **behaves on real devices, browsers and network connections**. Synthetic monitoring, by contrast, is better suited for regular checks that detect problems early. Both methods work well together: synthetic monitoring tests controlled scenarios, while RUM shows what real visitors experience. ## Where is synthetic monitoring used? Synthetic monitoring is used when a business depends on a website or application being available and performing reliably. It works well for simple websites as well as complex web applications. Common use cases include: ### Availability checks (uptime) An availability check is one of the simplest forms of synthetic monitoring. It tests whether **a website or service is online and accessible** at set intervals. Monitoring servers send simple requests to defined endpoints. If a server does not respond or returns an error code, the system detects an outage. Global checkpoints can also show whether the problem is affecting all users or only certain regions. Companies receive immediate notifications when downtime occurs, so technical teams can respond quickly and effectively. This also allows outages to be detected outside regular business hours. ### Performance monitoring Performance monitoring is another common use for synthetic monitoring. It measures **how quickly individual pages and resources load** to test the overall speed of a website. This includes DNS resolution, server response time and how long the page takes to render in the browser. Because the tests run under consistent conditions, the results are easier to compare over time. This helps teams see whether a website has become faster or slower and identify possible bottlenecks early. Teams can also more easily evaluate how updates, new features, or infrastructure changes affect website performance. Performance monitoring helps businesses maintain a fast and reliable user experience. It is also an important part of optimising a website’s performance. For a more detailed analysis of individual pages, tools such as [Google PageSpeed Insights](https://www.ionos.com/en-ie/digitalguide/online-marketing/search-engine-marketing/google-pagespeed-insights/) can also be used. Synthetic monitoring tracks load times and detects changes around the clock, while PageSpeed Insights provides specific recommendations for optimising performance. ### SLA monitoring Synthetic monitoring is also useful for monitoring Service Level Agreements (SLAs). Providers can use it to show whether defined **availability or performance targets are being met**. Because the checks run regularly under controlled conditions, they provide objective data that is not based on individual user experiences. If an SLA violation occurs, the exact time and possible cause can be documented. This gives customers more transparency and helps providers meet their contractual obligations. ### Release and change monitoring Synthetic monitoring can also help when new releases, updates or configuration changes go live. After deployment, automated tests can check key user actions, like logging in, completing a purchase, or submitting a form. This makes it easier to see whether important functions still work as expected. Any unexpected drop in performance also becomes visible quickly. Because the tests are repeatable, teams can compare results before and after a release and trace issues back to specific changes. This is a markdown version of: [https://www.ionos.com/en-ie/digitalguide/websites/web-development/synthetic-monitoring/](https://www.ionos.com/en-ie/digitalguide/websites/web-development/synthetic-monitoring/) for AI/LLM consumption.