Cramer's strong warning about IPO market

Cramer rains on IPO parade

The initial public offering deluge should be met with skepticism, Jim Cramer said Friday on CNBC, broadly comparing the new filings to the dot-com bubble of 1999-2001.

"I hate to rain on the parade. There's some really nice people going to make a lot of money," Cramer said on "Squawk on the Street." "But we are overtaxed by deals and I think if I don't sit here and say it, because I lived through 2000 and you just don't want it to happen again. You just don't want to."

Read MoreDespite uncertainty, more grist for IPO mill

Over the past three weeks, more than a dozen companies began trading on the stock market. On Friday, online food delivery company GrubHub saw shares jump more than 40 percent in its market debut. The Internet company priced its IPO at $26 a share on Thursday, giving it a value of roughly $2 billion. The price was slightly above an already raised expected range of $23-$25 per share.

To Cramer, GrubHub is profitable and some of these companies might be worth investing in. For the most part, though, Cramer thinks the recent IPO market largely feels frothy and without much skepticism.

There is no level at which the insiders won't sell these stocks after they go public, he warned. "There's a humongous amount of selling."

—By CNBC's Drew Sandholm.