Top 9 Y Combinator Application and Interview Tips You Need to Know

Getting accepted into Y Combinator is a watershed moment for startup founders who want to take their talents and big ideas to the next level.

Apart from the much-needed financial boost that enables startups to hit the ground running, the mentorship and networking opportunities YC offers can set up founders for success once their program is completed. 

But getting your foot in the door can be challenging, especially when you're likely competing with hundreds of other startup founders for a coveted spot in one of YC's biannual batches.

Filling out YC's online application, preparing an application video, and passing the in-person interview round with flying colors can be a time-consuming, if not daunting, experience for many early-stage founders.  

To help you develop a game plan that works for your startup, we've compiled a list of expert advice and insights from actual founders on creating a successful Y Combinator application. 

Pilot's Startup Evangelist Gillian O'Brien, Doppler Co-Founder and CEO Brian Vallelunga, and Kalshi Co-Founder and CEO Tarek Mansour share snippets of their YC experience with us and offer tips for anyone who's thinking of applying.

1. Brevity is Key

Knowing the ins and outs of your business is paramount, but explaining it to someone like your life story can also work against you. Extremely long-winded answers to questions on the YC application or during the in-person interview can do more harm than good.

"YC likes clear, concise communication," Gillian says. "They want to see that founders have a really good grasp on what they're doing, and the best way you can demonstrate that is by saying what you need to say in as few words as possible."

According to Brian, your response on your YC application or during an in-person interview should "really get right to the point" within the first couple of sentences. "If they are three sentences in and still don't understand what you're doing, they're going to move on to the next application," he explains. "You should also avoid using generic phrases like, 'We are a technology company that improves the world' — I have no idea what that means."

Since hundreds of founders are likely submitting applications for any given YC batch, there's only a limited amount of time for you to make an impression. "If they don't get what you do, it's going to be very difficult," Tarek says. "You need to put yourself in the position of someone who's truly going to give just four seconds to your first few sentences and probably glosses over them." 

2. Embrace the Ugly Truth

It's easy to feel like no one will want to invest their time, money, and effort into a business that isn't gaining traction or doing well. But let's face the facts: you're not where you want to be and need YC's help. You know that and as it turns out, so does everyone else at YC.

It can be tempting to play down the hardships and challenges that your company is facing, but it takes work to fool application reviewers and YC partners. 

"YC knows that your business is on fire, basically, and one of the first things they say, when you start the batch, is, 'We know that your business is very vulnerable,'" Gillian says. "Along with being clear and concise, I think the best thing to do is to be straightforward and honest about the situation that you're in."

For instance, if you're asked to explain how long you've been working on your company, don't try to over-explain by saying that you've had a business idea for the past three years, worked on it part-time for two years and then started working on it full time for the last two months. 

Keep your response simple in this case and say that you've been working on the business for the last two months.   

"Be confident and straightforward," Gillian says. "When you try to spin it or add a bunch of frills to an answer, it's just a little bit more obvious to the person reading the application that you don't think it's a very good answer. You're trying to say what they want to hear, which you don't need to do."

Since each YC partner knows specific industries well, the team as a collective whole will know when the founders are onto something. As a founder, your job is to briefly explain what isn't working within a specific industry and convey how your business will make it better, fulfill a need, or fill a gap in services.

Fluff that doesn't add much value and overt attempts to make your company look better can work against you.

3. Talk About Your Competitors

There's nothing wrong with competitors, but when your startup is just getting off the ground, it can be tempting to avoid or dance around the topic when trying to attract investors.

That's exactly what happened when Brian and his fellow co-founders made it to the interview round with YC partners. "They called us out for it in the interview," he recalls. "We then answered, 'We can live in the same space as our competitor, and that's fine. The market is big enough to handle both of us, and maybe at some point, we'll eat up their market share.'" 

Looking back on it now, Brian believes that response helped his team get into YC. "It's easy to get scared about that because they seem so big, but what you have on your side is speed and mobility, which is, arguably, sometimes even more powerful," Brian says. "If you have a unique perspective about the market and your competitor, that's powerful. So, for example, it's like, 'They're doing X, but we believe that the market needs Y, so we're just different.'" 

4. Know What Your X Factor Is

Whether you realize it or not, your team likely has some sort of unfair advantage — or advantages — over every other team. The challenge is to figure out what makes you — and your startup — uniquely qualified for YC. Once you've done that, focus on no more than two qualifications and drive the message home when you're writing an application, recording an application video, or even preparing for an in-person interview. 

"There's fatigue that goes on when you're reading these applications, so you want to double down on whatever it is that you choose and re-emphasize it throughout your application," Gillian says. "Keep coming back to the reason you feel is going to make you win."

As risky as it may sound, don't be afraid to "think differently than what the market is doing today," Brian says. "I think that's probably one of the strongest unfair advantages you can have," he explains. "If you think there's a competitor out there, they're not going to be able to change on a dime. They've mobilized their troops to go in a certain direction, and if you're going in a completely different direction that you think is better for the market, then that's a huge, huge advantage."

Although you seem to need some superpower or star power to stand out, what makes your company and team unique may be simple. In Kalshi's case, for instance, Tarek and his fellow co-founders believed they cared more than anyone else in their industry and were willing to go the extra mile to make their business work. "It could be a simple answer, but explain why as well," Tarek says. "It doesn't need to be a superpower; there are no superpowers. We're all pretty normal human beings, so it could just be something very simple." 

5. Lean Into Mischievousness

While a lot of attention is paid to the companies that came out of YC, it's worth pointing out that not all of them were conceived by founders before their batches started. For example, the founders of Segment (acquired by Twilio), Retool, and Brex had completely different startup ideas when they arrived at YC. However, with the help of YC partners, these founders eventually pivoted during their batch and started the companies we know today. "They came in with completely different ideas, but YC wasn't betting on their idea — they were betting on the founders to get to the right idea," Brian says.

With this in mind, taking advantage of opportunities that let YC partners see who you are as a person is essential. "Being a little mischievous — maybe knowing where the line is and getting close but not crossing it — and those kinds of things can highlight you as a person and some attributes they may be looking for, so go big and bold on it," Brian says.

For example, The Muse Co-Founder and CEO Kathryn Minshew has spoken about her interesting response to this question on YC's application: "Please tell us about the time you most successfully hacked some (non-computer) system to your advantage?" In The Muse's YC W12 application, Minshew explained how she only paid for a hotel room once during a 77-day trip around the world and somehow talked her way onto a plane that departed 12 minutes after she arrived at the airport. 

"I think YC wants to see that you're curious and have some gumption and creativity," Gillian says. Those things come out when you can show that you've hacked something, as long as it's wholesome, not exploiting anyone or breaking the law. 

If you're thinking about how your personality can shine through, consider that founders shouldn't be afraid to take risks, think outside the box, and push the envelope a little. For example, it would help to list your business ideas on that part of the YC application since it may be an unexpected way to showcase who you are. While founders may be worried about people thinking their business ideas aren't good, it's essential to take a leap of faith anyway. "Just go all in and list them all because it's an opportunity to show your curiosity and a little bit of your personality, too," Gillian says.

6. Get a Recommendation From Someone You Know

Getting a recommendation from someone in the YC community can go a long way when applying for a batch slot. Although a recommendation isn't required or necessary to apply to YC, having one on your application is always a good idea. The caveat is that you should know someone well before asking them for a recommendation. Randomly asking for a recommendation from anyone affiliated with YC or founders from previous batches isn't going to get you very far. 

"Don't ask people who you don't know very well or at all," Gillian says. Ask people who you know well and can vouch for you. That's going to be very good." 

7. If You Get Rejected, Keep Applying

Not getting accepted into YC can be hard to swallow, but it doesn't mean you should give up hope. After all, there are two opportunities every year to apply for a slot in YC's summer and winter batches, and a fair share of founders who got in were rejected several times before they were ultimately accepted.

Applying multiple times can testify to your perseverance, determination, and passion. "I don't think there are any rules around when and how to apply, and there's no internal rules at YC," Tarek says. "They would love to see your application four or five times any year."

Brian, for instance, applied to YC six times before finally getting accepted on his seventh try. "It took me seven times to get in, so it's proof that you can do it," Brian says. 

8. Avoid Cliche Comparisons

During YC's early years, one of its co-founders, Paul Graham, wrote a comprehensive guide on how to apply to YC and offered a "good trick for describing a project concisely."

"Explain it as a variant of something the audience already knows," he wrote. "It's like Wikipedia but within an organization. It's like an answering service but for email. It's eBay for jobs. This form of description is wonderfully efficient. Don't worry that it will make your idea seem 'derivative.' Some of the best ideas in history began by sticking together two existing ideas no one realized could be combined."

The problem is that several YC applicants have likely used this safe yet effective approach over the years. To really stand out, applicants should be bold and original. Latching on to a movement or trend may help people understand your business, but you need help to break away and develop something game-changing. "They're not looking for those founders who are looking for cheap, easy wins," Brian says. "They're looking for founders who are thinking differently about a market. So they're going to build something big. If you think about where YC makes its money, it's on the couple companies that make it extremely big, and they did that by thinking about things very differently."

9. Show the Scale of Your Ambition

Determining the size of your market can be particularly difficult, especially if you occupy a unique place within one or want to do something very different. In these cases, it can be more advantageous to explain where you want to be and what that will look like later on down the line. 

"If you really are the breakout success that we all want you to be, you're probably going to be impacting the market," Brian says. "The market will grow just by your being in it, so I think this is an opportunity to be super transparent and share how you think about things."

Though figures and estimates can help you quantify the impact of your business on the market, trying to paint a vague or ambiguous picture of what that would look like won't be helpful in an interview. Instead, thinking about how far you want to go and where you want to land may be more useful. "In some ways. I feel like they don't even want to know your market's size," Tarek says." Instead, they want to know what the scale of your ambition is."

Turn to Pilot for More Advice

Remember that YC partners invest their time, money, and energy into founders like you. So whether you're filling out your application, filming your application video, or even preparing for an in-person interview with YC founders, keep some best practices in mind by concisely articulating who you are, what your team is working on, and where you want to be in the future.