Tools for testing Web sites

There are no amazing tools on the market that "do it all" for testing Web sites. There are significant pricing and licensing difference in the types of tools you're seeking. Link checking tools fall into a utility category while performance tools fall into a far more sophisticated application category requiring different licensing and maintenance considerations. My suggestion is to clarify your needs and then seek a solution and/or appropriate tool for each need.

Grammatical errors:
I would check content in a word processor before posting content to the site. I don't know of anyone who purchases a tool to check a Web site for grammar although there may be tools available in this area that I'm unaware of. I would check the content and then push clean content online.

For both link and grammar checking, you need someone whose responsibility is to run the tool and check for errors at key intervals. There was a point where I personally was the link checker for a production Web site -- I committed to a weekly check which worked well for our environment. In my experience, it's not the tool that's the challenge in these areas because the cost and complexity is usually simple. It's the time; make sure the task belongs to someone.

The other challenge is communication, here's an example. If multiple people make edits to a Web site, then when and by whom should content be checked for grammar? In one environment, we had one person designated to push changes even though many people made content edits -- that same person was a good choice for a grammar sanity check. Buying tools won't resolve embarrassing Web site errors. Assign someone the task and make sure the task doesn't drop off their list during busy times -- assigning the task can be more important than buying a tool.

A final comment on utility applications -- they change frequently. Small, simple tools are often underfunded and become obsolete quickly. The link checking tool I used a few years ago is no longer on the market and the vendor no longer exists either. I usually assign the person who owns the task to also own the tool which includes keeping an eye on the tool and the vendor. I believe occasionally checking the marketplace for better tools and better pricing is part of owning the task but be clear about all the responsibilities when you assign a task.

Performance testing tools and resources: Developing an approach to performance testing How to evaluate testing software and tools Testing Web applications for performance

Performance testing:
This is a more sizeable consideration. What performance testing do you want to conduct? Who in your company wants performance testing to be executed? I have more questions than I have answers for your question about a performance tool because if you "simply get a tool" you'll be setting up expectations that significant body of work will be executed. Do you have the staff? What tool does the staff have experience with? Identify the work, figure out who (resources) will address the testing, and get discussions started on expectations

Don't buy a tool until you're ready. Once you buy a tool, the clock starts ticking with people's expectations. Performance testing is a considerable effort and often comes at a considerable cost in terms of people talented enough to design, build, and execute the test then add the cost of a tool. Choosing the tool isn't difficult because there are only a few tools in the marketplace and a few queries in Google will list the vendors. It's my impression from how you asked this question -- by lumping a performance tool with a link checking tool -- implies to me that you and your company aren't ready for the purchase phase of a performance tool. I'd recommend gathering an understanding of performance testing needs and wants before purchasing a tool.

You listed "etc." for testing a Web site and I'm guessing you're looking for other utility-type applications to care for and test a Web site -- with no further clarification -- there are no other tools I can recommend to you.