Paste a URL and get your landing page reviewed through four different YC partner lenses — communication, conversion, distribution, and the idea underneath. Pick a partner, or run all four over the same page.
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Pick a partner
Four lenses, four different questions about the same page: does it communicate, does it convert, does it have a customer, and is there a real idea underneath. Switching partner does not lose your URL or the review you are reading.
Paste any URL
We load that one page — its text, its markup, a screenshot, and for two of the lenses the type sizes and colours the browser actually resolved. No login and no email.
Run more than one
The four disagree on purpose. A page that passes the design review can fail the idea review outright, and that gap is usually the most useful thing you learn here.
The instinct when building something like this is to blend every lens into one — take the four partners, average their advice, and ship a single “YC review”. We tried the thought and rejected it, because what makes a review useful is a specific opinion applied consistently, and the average of four opinionated reviewers is the bland page critique you can already get from any free checker.
So they stay separate, and they contradict each other. The design lens can pass a page that the idea lens fails outright. The conversion lens will tell you to cut a section that the distribution lens says is the only evidence you have talked to a customer. That gap is usually the most useful thing on the page.
A landing page fails in four fairly distinct ways, and most teams only check for one of them. It can fail to communicate, so nobody understands what you sell. It can communicate perfectly and still lose people between the headline and the product. It can convert well for a visitor who will never come back, or who was never going to be found in the first place. And it can do all three competently on top of an idea nobody needed.
Each partner lens here is built around one of those failures, which is why running two is worth more than running one twice.
Every test in every lens has to be answerable from the page itself. That constraint costs some of the best ideas each of these partners has — the growth lens has no access to your retention curve, and the idea lens cannot tell you whether your market is big enough. Asked to judge those anyway, a reviewer invents something that sounds right, and an invented finding is worse than a missing one.
So the lenses are narrowed to what a page can evidence: the segment it names, the steps it costs, the problem it states, the claim it makes. Where a question needs a dashboard to answer, it is not in the lens, and the review says so rather than guessing.
Superflow is not affiliated with Y Combinator, and none of these partners has reviewed your page or endorsed this tool. Each lens is our interpretation of material the partner or YC published publicly — the Design Review series, Startup School talks, essays — and every source is cited under the result so you can check the interpretation against the original. No lens here writes in the first person as anyone, and none of them will produce a quotation.
No. Superflow is not affiliated with, endorsed by, or connected to Y Combinator or any of its partners. These are review lenses we built from material YC and the partners published publicly, and every source is cited under the result so you can check our work against it.
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Superflow agents review the pages you ship on every change, against the standards your team actually holds, and leave the findings as comments on the page itself.