I was contacted within a few days after submitting my application for the testgorrila assessment. Didn't start it until 6 days later after a follow-up by the HR team. The assessment took 30 minutes, with 2 parts in Detail attentiveness (spotting differences, punctuation, spelling, and so on) and Data analysis (interpreting graphs). The assessment was overall easy, I landed in the 90ish percentile. Right the day after, I got contacted for inputting availability for the next 2 weeks. And got an interview date and time very quickly the next business day.
Negative experience
Average interview
Application
I applied online. I interviewed at BillionToOne (Menlo Park, CA) in May 2026
Interview
One online quiz, zoom interview with a lead CLA, zoom interview with the associate director of lab operations, zoom interview with the department team, an in person interview with a lab practical that they'll reimburse for travel expenses, a final interview with the senior vice president of lab operations, and one more zoom call where they review the offer with you. The process was extremely drawn out and long. Some of the questions felt really repetitive. I'm pretty disappointed that after that whole process they wouldn't negotiate pay with me and only offered a sign-on bonus.
Interview questions [1]
Question 1
The lab practical was a one page set of instructions on how to prepare mastermix (they were changing the protocol on the intended practical that day so it might be different from mine). You get your needed reagents labeled on a rack and you mix them based on the volumes provided on the instructions.
I applied online. The process took 4 weeks. I interviewed at BillionToOne (Union City, CA) in Apr 2026
Interview
The interview process started with a virtual assessment through TestGorilla, followed by a Zoom interview with a senior Clinical Laboratory Associate. After that, I was invited to a three-hour in-person interview. The onsite interview included two back-to-back 30-minute interviews and a lab practical. For the lab practical, the SOP they give you is very short and doesn’t explain much. You’re basically instructed to pipette different volumes of liquid (it’s just water) into tubes in a specific order. The main thing they’re testing is whether you can follow directions carefully and handle pipettes correctly. After mixing, you place the tubes on a vortex (the vibrating machine) to mix them, and then use a centrifuge (the machine that spins) to bring everything down to the bottom of the tube. It’s meant to simulate basic PCR prep, but it’s more about attention to detail than actual science knowledge.
