One of the Most Highly Rated GMAT and GRE Tutors
William Brubaker has top ratings by his GMAT and GRE students and positive reviews like the following:

  • Emily on 7/8/2019 Good news! I wanted to share an exciting update regarding my business school journey. I am excited to let you know that I have been accepted to Pepperdine's Part-Time program and will be starting Fall 2019! Thank you again for all your help with studying for the GMAT. The rigorous study schedule has helped me to prepare for the semesters ahead.
  • Malcolm on 5/28/2019 Hi William! The exam went well. I scored a 700, and saw a lot of improvement in Quant. I’m comfortable with that score (as it is within my range). Thanks for your help!
  • Avi on 5/4/2019 Got off waitlist at London Business School. Just wanted to share!
  • Ideen on 3/26/2019 I'm excited to share with you that I was admitted today to USC and Georgetown MBA programs (and am waiting on some more decisions). Thank you so much for working with me on improving GMAT score!
  • "William is a helpful and professional tutor with a solid system in place. The software that he uses is helpful and helps to save time and keep his students on track.
  • "Update" - Saniya on 1/2/2019 Just wanted to give you an update - while I’m still waiting on some of my R2 schools, I’ve gotten into Kellogg and NYU R1, with an interview at Columbia :) Kellogg is one of my dream schools, so I’m really excited about that one!  Couldn’t have done it without your GMAT help - thank you so much for that!
  • "Best tutor I've ever had." - Ryan on 11/27/2018 William is an excellent tutor. He goes out of his way to make sure I understand each problem before moving on. William has incredibly effective teaching methods, including reviewing and practicing problems as "homework". My practice tests have improved significantly since I began tutoring with William  and my GMAT test will show these same improvements. Highly recommend.
  • "Excellent GMAT Platform" - Evan on 6/18/2018 William is a very patient and knowledgeable teacher, he takes the time to teach each new topic as they come up. He allows you to utilize an efficient and effective study plan to supplement your own. I have had several sessions with him and would highly recommend him!
  • "Very patient and easy to understand" - Nando on 3/27/2018 William helped with my GMAT Quant section. He reviewed data sufficiency questions as well as helped me to refresh my algebra and probability problem areas. He was indeed very patient and questions were directed at figuring out my knowledge base and building from there
  • "Very knowledgeable, very patient GRE tutor" - Elizabeth on 3/13/2018 William is helping me VERY much with the math portion of the GRE. It's been 15 years since I've done high school algebra and geometry, and I've forgotten almost all of it. He's tailored his lessons for exactly where I'm at, and even assigns extra practice in between tutoring sessions to help me catch up. So grateful for his help!
  • "Knowledgeable and Patient Tutor" - Pat on 1/27/2018 Thus far, William has honed in on my weaknesses and helped me mitigate the behaviors that are detrimental to scoring in the 700s. I look forward to my continued work with William.
  • "Excellent tutor with real GMAT knowledge and individually tailored lessons" - John on 12/6/2017 I took about a dozen lessons with William over the course of two months, and he helped me pull my GMAT score up from 660 to 710, with what felt like minimal effort from me. His online meetings work great, and he tailors the questions you receive so that they are appropriately challenging. He also provides optional homework, so that the lessons can be spent reviewing questions you know you need help on, rather than just working on questions with him there if you need him. He has great insight and tips for the GMAT, and I doubt there is a better instructor out there.
  • "Great tutoring method, very effecting, helped me raise my score by 50 pts in 6 lessons" - Mike on 10/31/2017 William is a patient tutor. He helped me hone in on my weaknesses and really improve my quant concepts and skills . I improved my GMAT score and was accepted into my #1 choice. I highly recommend William for GMAT tutoring.
  • "Patient, knowledgable, and effective tutlr" - Harrison on 10/13/2017 William was a godsend for GRE prep --- he broke down the concepts and provided plenty of problem sets to help you get the score you want. I would 100% recommend him to anyone looking for a quality GRE/GMAT tutor.
  • "Great process for helping you focus on the areas you need help the most" - Ryan on 9/30/2017 I worked with William over the period of several months. He helped me significantly improve both my quant and verbal scores helping me achieve a higher score than I was even targeting. William is patient and flexible, willing to accommodate your needs and requests and work around your schedule. I recommend William for any GMAT tutoring.
  • "Very patient and explains in detail" - Demonte on 8/25/2017 I was comfortable knowing that William would guide me through the material and teach me ways of processing these questions.
  • "Exactly What I Needed, Just in Time for the Exam" - Zach on 7/17/2017 TL:DR William has a practiced, methodical system in place to improve your score. He takes you where you are and develops your skill from there. I went from a Manhattan Prep practice test low score of 630 to a test day score of 730 (45Q, 46V). Read on for more details: When I came to William for tutoring, I had all background material read and about a month of practice problems under my belt from both Manhattan Prep and an Official Guide (think 200+). However, my scores up to that point were 710, 640, 630, and 680 on Manhattan Prep tests. While MP tests are known to be more difficult than the real thing, with 700+ as my goal and my test scheduled a month away, I wasn't sure what to do. William took me where I was and built my skill from there. The first lesson is very constructive and consists of finding your current percentile, whether 1st or 99th. You offer your target score, and William candidly assesses how realistic the goal is given the time frame. After that initial lesson, you set up a schedule (William was very accommodating. I felt bad one week when he agreed to a lesson on Saturday AND 4th of July) and off you go. You complete practice problems under his supervision during the lesson and you get a set of explanations to review and homework to complete after each session. What I felt most helpful was the ability to think out loud. I knew the GMAT could be cracked, but it felt like I was missing some important piece of the puzzle. Doing practice problems on my own did not allow me to identify where I was thinking an incorrect way or heading down the wrong path. The hardest part about the GMAT is identifying what the test really wants you to see about a problem and dissecting its components & difficulty. William was able to jump in after I hit a wall or redirect if I was heading down the wrong road. Apart from this mid-problem assistance, his explanations offer shortcuts and insights I never encountered in other resources. His way of thinking about things shone light on new techniques and ways to concept problems. After 4 weeks of these lessons (and reviewing the explanations in-depth and completing the homework), and additional practice test scores of 710, 720, 680, and 740, test day arrived on July 8th. Very happy to report a score of 730 on test day! 45Q, 46V. Thank you for all your help, William!
  • "Efficient and disciplined tutor for GMAT Quant - RESULTS!!" - Thomas on 3/30/2017 William has a really useful bespoke system for diagnosing and addressing weak areas in GMAT. He helped me move from 39 to 48 on Quant in two weeks. An insane improvement made possible by William's streamlined approach. Online sessions can be really valuable it turns out!! Also William is a super friendly, agreeable guy :)
  • "Clear and Knowledgable" - James on 3/9/2017 After my first session with William, I felt more confident about approaching questions. As a result, I improved the % of questions I was getting right. I am looking forward to continuing to learn from William.
  • "Very patient" - Diego on 1/28/2017 Has a great platform that costumizes the work according to your level in each section of the exam. The platform also allows you to go back to your lessons and make some practice questions.
  • "Knowledgeable" - Sasha on 1/27/2017 Very well structured session. We worked on strategies for the logic portion of the exam. Looking forward to our next session.
  • "A very thorough tutor" - Brandon on 1/24/2017 Working with William you really feel that he's leaving no stone unturned. I'm working with him to prepare for the GRE exam. Between the material he provides outside our lessons to study and what we actually go over in our lessons, it's a really complete package.
  • "very knowledgeable and high quality tutor!" - Michael on 12/2/2016 William is an exceptional GMAT tutor who not only knows what he is doing, but has a very sophisticated lesson plan that I have not seen before. William is able to hone in on questions based on difficulty type and scale up difficulty as will. Really knows his methodologies so it's not only about how to do a problem but why certain strategies work and don't work.
  • "Great Lesson!" - Alexandria on 8/30/2016 After just one lesson I am really starting to feel like I understand where I am going wrong with the GMAT. Thanks William!
  • "Patient tutor with great impressive online question bank" - Adeela on 7/23/16    – I had a month to get my GMAT quant score up. I was testing a 39-40 and in just a month working with William & going through practice questions in his online question bank, I was able to raise my score to a 47. For a liberal arts student who hasn't taken a math class in over 10 years, I'm more than happy with my results -- scoring a 720 cumulative should hopefully help me get into my top choice schools! If you're willing to put in the time & study hard, William can definitely help you improve!
  • "First Session Review" - Angela on 7/8/16    – William is helping me analyze data sufficiency, probability, and reading comprehension problems. He is very helpful in breaking everything down to steps that are easy to understand. He also sends cues after every lesson to review. Overall, extremely helpful.
  • "Very Patient" - Brandon on 6/8/16    – Once again we had a great session. He is very patient and explains the reason for certain answers very well.
  • "Very to the point" - Alexis on 5/31/16   – Jumped right into problem solving and discussed any problem areas at length. I have some anxiety when it comes to tests like the GMAT, but William doesn't really leave any time/room for being nervous or second guessing. Each session is packed with problem solving and after 2 hours I feel like a lot has been accomplished. Recommend William for anyone who has a working knowledge of the basics, but who needs repetition and deeper knowledge of the processes or the logic behind the answers. It's a vital skill to have, because problem recognition will come much faster, even when the questions are worded differently or have a higher degree of difficulty.
  • "Highly recommend!" - Rassmussen on 4/5/16   – Bill has a very systematic way of figuring out how best to help someone preparing for the GMAT. I would highly recommend Bill to anyone looking for an excellent tutor.
  • Lynn on 3/30/16   – I wanted to share the good news with you: I just got into Harvard business school this morning! Thank you SO much for all of your help on the GMAT – I could not have done it without you.
  • “Great System” – Andrew on 2/18/16 –  William did a great job explaining material over the one lesson we had. Certainly a good fit for anyone looking to improve GMAT score
  • “Great tutor for rusty students” – Brian on 12/29/15 –  After 4.5 hours of one-on-one lessons with William I was able to raise my GMAT score 70 points. Worth every penny! Graduated college 6 years ago.
  • “An Absolute Game Changer!” – Sarah on 10/25/15 –  William did not have it easy trying to help me study for the GMAT! He had to go back to the beginning on a lot of math techniques but his program with both visual explanation and being able to talk your through it is the only reason I feel I am starting to regain some knowledge of math, and a better understanding of English!
  • “Bill is a phenomenal tutor!” – Lynn on 9/28/15 –  As someone who had taken the Manhattan GMAT course, I was hesitant to try a tutor in fear of re-learning what I had already learned. However, Bill was able to adapt to my needs and tailor me to the harder questions in his program. He is incredibly patient, intelligent, and adaptable. What I appreciate most about him is his constant efforts at improving and tailoring his program to your needs. He was constantly evolving his system to best suit his students' needs and was incredibly receptive to feedback. My score improved nearly 100 points under his tutelage. I highly recommend him to anyone, regardless if you have taken a course already. He was definitely worth the investment and I consider him a tutor, mentor, and friend!
  • “Great tutor!” – Ian on 6/30/15 –  William has been able to identify my key weaknesses that has helped me make serious improvements in my GMAT capabilities.
  • “Great tutor and very attentive to student’s needs” – Freya on 12/3/14 –  William is a very patient tutor who explains things according to the student’s pace. He is incredibly smart and really understands what he’s talking about. Choose him if you have been searching for the perfect tutor for you GMAT preparation!
  • “Improved my score!” – Vivian on 7/17/14 –  William helped me improve my score 80 points. I was very pleased with the results. I had been struggling on improving but it all paid off. I am thankful I found him.
  • Hugh on 5/8/14 –  I worked with William in preparation for taking the GMAT. It had been 15 years since I last took a math class, so needless to say, my math skills for standardized testing were more than a little rusty. After 8 2-hour sessions with William and some hard work, I was able to raise my score by 130 points, from a 600 on my first diagnostic test to a 730 on test day, in less than 2 months. He was flexible with my schedule, easy to work with and highly effective. I recommend William wholeheartedly.
  • “Great GMAT Tutor” – Sarah on 2/25/14 –  Bill worked with me for a total of 30 hours and was always flexible with my work and personal schedule. About a year ago, I had taken the in-person Manhattan GMAT course, which is supposed to be the top GMAT program. After I completed this course, I took the GMAT a couple times but never reached my target score. Bill was understanding of my needs and weaknesses and he patiently worked to help improve my math percentile from a 36% to 63%. He provided weekly study guides and practice questions. I can’t thank him enough and would recommend Bill to any student looking for math or verbal help, especially those looking for an engaging and intelligent GMAT tutor.