# Load Testing With Real Browsers, on a Site You Own > Load test your own site with real browsers that load every asset and run its scripts: a worked setup, what to watch on the server, what other tools do better. A request generator sends requests; a real browser also loads scripts, images, fonts and third-party tags, and calls your APIs the way the front end does. Traffic Generator puts that kind of load on your site at the volume and in the hours you choose, so you can watch the server, the CDN and the database before real visitors arrive. Point load only at sites you own or are authorized in writing to test. The Terms of service forbid using YOOtraffic to overload a third-party site. ## What Browser Load Tells You ### Load from the whole page 01 - A request generator measures how fast the server answers a URL. A browser session also downloads every asset, runs the page's JavaScript, triggers the API calls the front end makes and fires each third-party tag, so it tests cache rules, the CDN and the scripts as well as the origin. - That makes it a good check of a new release, a move to a new host or CDN, or a template that added heavy scripts, with the device and browser mix your visitors actually use. ### What it does not replace 02 - Traffic Generator sets how many sessions arrive in a day and in which hours, not an exact requests-per-second ramp. For a stress test to the breaking point or a precise concurrency curve, use a protocol tool such as k6, JMeter or Locust next to it. - A workable split: the protocol tool finds the ceiling of each endpoint, and the browser sessions show how the full page holds up at the traffic you actually expect. ### Only on your own site 03 - Run load only against a site you own or have written permission to test, and check whether your hosting provider asks for notice before a load test. The Terms of service forbid using the service to overload any third-party site. - Start well below the level you are worried about and raise it between runs, so a problem shows up as a trend in your graphs rather than as an outage. ## Example: A Launch Rehearsal A store is moving to a new host before a seasonal sale and wants to see how the new setup handles a busy evening. The rehearsal runs a compressed version of that evening against the new host, with the store's own monitoring open. Campaign settings ### Target URL The home page on the new host, with paths through category and product pages ### Volume and schedule 2,000 sessions concentrated in 2 hours, about 17 new sessions a minute ### Session duration 180 to 300 seconds ### Page depth 4 pages per session, about 8,000 page loads in all ### Devices The mobile and desktop split your analytics shows for the store ### Country The country the sale is aimed at ### Traffic source Direct, so the run is easy to separate from campaigns in analytics What to watch during the run - Response time per path in the access log, such as the request time field in nginx, at the median and for the slowest 5 percent - The share of 5xx responses and timeouts, per path - CDN cache hit ratio: a page that should be cached but reaches the origin on every load shows up here first - CPU, memory and open connections on the origin and the database, and the slow query log - Errors from third-party scripts and from the API calls the front end makes Cost of the rehearsal: a range of 180 to 300 seconds is billed at $0.0024 a session, the average of the prices of the shortest and the longest session in the range, so 2,000 sessions cost $4.80. ## Running a Load Rehearsal ### Record a baseline Note response times, error rate and resource use at normal traffic, for the same hours of the day, before the first run. ### Start at a fraction Run the first batch at a fraction of the target, read the graphs, then raise the volume for the next run. Change one thing between runs: the volume, the hours or the pages covered. ### Watch, and stop if you need to Keep the dashboards open while the run is on. A campaign can be paused at any moment, and paused time costs nothing. ### Compare with the baseline Set each metric from the run against the baseline. Which one degrades first, and at what volume, is the result of the rehearsal. ## What Browser Load Covers and Where a Protocol Tool Takes Over - Puts full page loads on a site you own: assets, scripts, API calls and third-party tags, from real browsers - Lets you set the daily volume, the hours, the device mix and the paths, and repeat the same run after a fix - Shows how the origin, the CDN and the database behave at the traffic you expect, in your own monitoring - Does not give an exact requests-per-second ramp or a breaking-point stress test: a protocol tool does that - Does not test sites you do not own or are not authorized to test: the Terms forbid overloading third-party sites - Does not test sign-in or checkout: the sessions do not log in, fill in forms or pay ## Tool Used in This Example The sessions come from Traffic Generator, billed per session at a rate set by the session duration you configure. The full rate table is on the pricing page. ## Load Testing Questions ### Can I load test a staging site? Yes, as long as the browsers can reach it: the address has to be publicly reachable, and the sessions open it the way any visitor would. A staging copy with its own analytics property also keeps the run out of your production reports. ### How many sessions can I send? There is no daily cap: you set the volume per day and the hours it runs in. ### Will the run show up in my analytics? Yes. The sessions run your analytics tag like any page load, so they are counted. With Direct as the source and the run's hours written down, the spike is easy to filter out of later reports. ### Why not use k6 or JMeter alone? They are the right tools for finding an endpoint's ceiling. Most protocol tools do not run the page's JavaScript or load its third-party tags, and running the browser modes some of them offer at volume takes either your own machines or a paid cloud plan. Browser sessions cover that gap at the traffic you expect. --- - HTML version of this page: https://yootraffic.com/en/use-cases/load-testing - Site index for agents: https://yootraffic.com/llms.txt - Sitemap: https://yootraffic.com/sitemap.xml