Is it grammatically correct to say similar to?

Yes, "similar to" is grammatically correct. It's a common phrase used to compare things that share similarities.

Here are some examples:

* "This painting is similar to one I saw in the museum."

* "The weather today is similar to yesterday."

* "Their ideas are similar to ours."

However, it's important to note that "similar to" is often used interchangeably with "like," but there's a subtle difference:

* "Similar to" emphasizes a degree of resemblance or likeness.

* "Like" simply suggests a resemblance without necessarily implying a close similarity.

So, while both are grammatically correct, the choice between them depends on the nuance you want to convey.