Reviews.Com reviewed 68 dating sites. At the end of the day they stated OkCupid was the best, which I have been saying for years.
The main reason okcupid is considered the best is the algorithm which matches people performs better than all the other sites.
Reviews.Com had the following to say about okcupid's algorithm.
OkCupid’s algorithm stands out because, while most online dating sites rank you as more compatible with someone if you both answer a question the same way (and less compatible if you answer it differently), OkCupid lets you choose what you want your potential match to answer — and how important that answer is.
For example, on OkCupid, we answered “no” to the question, “Do you ever intentionally try to make people angry just to see how they react?” Any algorithmic dating site would pick up on the fact that we would be more compatible with someone who also answered no to that question. And indeed, we chose “no” as the answer our partner should give (and marked it very important). But sometimes the “both answer the same way” approach doesn’t work so well. One OkCupid question asks, “How would you describe your body?” Our tester chose “slender” — but that’s not necessarily the answer she wants a potential date to give. In reality, she doesn’t care very much about body type at all. OkCupid let her specify that her possible partner could choose any answer: slender, average, athletic, or voluptuous.
Both Reviews.Com and my data has found that using okcupid's algorithm can lead to strong matches and high quality dates. The excerpt above is just a very small piece of the large story that is reviews.com comprehensive dive into online dating sites. If you want to read the whole article, click here.