Metacritic is a website that collates reviews of music albums, games, movies, TV shows, DVDs and books. For each product, a numerical score from each review is obtained and the total is averaged. An excerpt of each review is provided along with a hyperlink to the source. Three color codes of Green, Yellow and Red summarize the critic's recommendation. This gives an idea of the general appeal of the product among reviewers and, to a lesser extent, the public. (For examples of other such sites, see .)

The site is somewhat similar to Rotten Tomatoes, but the scoring results sometimes vary drastically, depending on which reviews are tallied. For instance, Rotten Tomatoes gives an overall unfavorable rating to Kenneth Branagh's film version of As You Like It by quoting mostly British critics, who reportedly have strongly disliked Branagh's Shakespeare films. Metacritic on the other hand, tallies its score largely from American reviews of the film.

Also, unlike Rotten Tomatoes, which aggregates reviews using a binary score of "fresh" or "rotten" for each review, Metacritic converts each review into a percentage before taking a weighted average. This can lead to more accurate results when reviews are unusually consistent, or there are only a few of them, but also opens up the possibility of reviewers 'gaming' the system, lying about their own perceived rating of the film in order to bring the Metacritic rating into line with it.

Many review websites give a review grade out of five, out of ten, out of a hundred, or even an alphabetical score. Metacritic converts such a grade into a percentage. For reviews with no explicit scores (for example, Amazon's reviews), Metacritic manually assesses the tone of the review before assigning a relevant grade. Reviews from certain publications also have a marginally greater influence on the average. One common drawback of Metacritic, however, is its lack of book reviews; following the release of Harry Potter and the Deathly Hallows, their regular coverage of recently released books ceased, except for major releases.

Metacritic was founded in 1999, and in August of 2005 was acquired by CNET Networks.