Selenium: Is there a performance difference between By.Id("myelement") and By.Css("#myelement")?
By.cssSelector() is faster than By.id().
The method to find elements using By.id() actually utilizes xpath:
@Override public List<WebElement> findElements(SearchContext context) { if (context instanceof FindsById) return ((FindsById) context).findElementsById(id); return ((FindsByXPath) context).findElementsByXPath(".//*[@id = '" + id + "']"); } @Override public WebElement findElement(SearchContext context) { if (context instanceof FindsById) return ((FindsById) context).findElementById(id); return ((FindsByXPath) context).findElementByXPath(".//*[@id = '" + id + "']"); }Where as By.cssSelector uses the CSS engine. CSS is faster than xpath, ergo, By.cssSelector will operate faster than By.id