Mike Holt accuracy test (review 5)

Why I Ran This Test

Mike Holt's materials built a generation of electricians. His videos, textbooks, and seminars are legendary for a reason. When I started building Ask BONBON, I kept hearing the same question from guys on the jobsite: is this thing as accurate as Mike Holt's stuff? Fair question. So I ran it.

I pulled 40 questions across the code book, from grounding to motor calcs to GFCI locations, and compared Ask BONBON's answers against Mike Holt's published answer keys and his Understanding the NEC reference series. Here's what I found, honest.

The Test Setup

I picked questions from five high-traffic areas where field guys get burned: branch circuit calcs, GFCI and AFCI requirements, grounding and bonding, motor and transformer sizing, and working clearances. I scored each answer on two things. One, did it cite the correct article? Two, would a journeyman on the floor be able to act on the answer without a second source?

No cherry picking. If Ask BONBON whiffed, I wrote it down. If Mike Holt's material was clearer, I said so.

• Branch circuit and feeder calcs: 10 questions
• GFCI/AFCI (NEC 210.8 and 210.12): 8 questions
• Grounding and bonding (NEC 250): 10 questions
• Motors and transformers (NEC 430, 450): 8 questions
• Working space and clearances (NEC 110.26): 4 questions

Where Ask BONBON Matched Mike Holt

On straight code citations, the two were effectively tied. Ask BONBON nailed the GFCI locations in NEC 210.8(A) including the 2023 update pulling in basements and the 6 foot rule around sinks. It got the 125 percent continuous load factor in NEC 210.19(A) right every time. Motor overload sizing from NEC 430.32 came back clean, including the 115 percent vs 125 percent split based on service factor and temp rise.

Grounding electrode conductor sizing per NEC 250.66 and Table 250.66 was correct on all ten grounding questions. Bonding jumper sizing from Table 250.102(C)(1) also checked out. These are the questions that eat apprentices alive on the Journeyman exam, and both sources handled them well.

Field tip: when you're sizing a GEC to a ground rod, it never has to be larger than 6 AWG copper per NEC 250.66(A), even if your service is 800 amps. Guys over-size this constantly and waste copper.

Where Mike Holt Won

Holt's strength is the worked example. When you're trying to learn a concept cold, his step by step math on a 3 phase feeder calc or a transformer secondary OCPD problem is hard to beat. His illustrations of the grounding electrode system are some of the clearest in the industry. If you are studying for a license exam, his material is still the gold standard for teaching.

Ask BONBON gave correct answers, but on two of the transformer secondary questions, the explanation was thinner than Holt's. A first year apprentice might need Holt's longer walkthrough to understand why the answer is what it is. For a journeyman who already knows the concept and just needs the number, Ask BONBON was faster.

Where Ask BONBON Won

Speed and job site usability. On a ladder with one hand free, you can't open a 400 page PDF and ctrl-F. Ask BONBON pulled the exact working clearance depth from NEC 110.26(A)(1) Table in under two seconds. Mike Holt's answer is in there too, but you have to find the chapter, flip to the table, and read around it.

Ask BONBON also handled context-dependent questions better. When I asked about GFCI protection for a dishwasher in a dwelling vs a commercial kitchen, it correctly split the answer between NEC 210.8(A)(6) and NEC 210.8(B), and flagged that the commercial requirement pulls in more circuits. That kind of branching answer is where a searchable tool beats a linear textbook.

1. Average lookup time, Ask BONBON: 4 seconds
2. Average lookup time, Mike Holt PDF: 38 seconds
3. Average lookup time, printed Code Book with index: 52 seconds

The Honest Score

Out of 40 questions, Ask BONBON got 39 code citations correct. The one miss was on a feeder tap rule under NEC 240.21(B)(2), where it cited the 10 foot tap rule but didn't flag the termination requirement at the far end. Mike Holt's material caught that detail. I've since logged it as a training gap and the answer is now correct.

Mike Holt's materials scored 40 out of 40, which is exactly what you'd expect from a reference that has been edited and reviewed for decades. The gap is narrower than I expected, and for the specific job of looking up a code answer on site, Ask BONBON was faster on all 40.

Bottom line from a working electrician: use Mike Holt to learn the code, use Ask BONBON to work the code. They solve different problems.

What This Means For You

If you're prepping for your journeyman or master exam, buy Mike Holt's Understanding the NEC. No tool, including mine, replaces that kind of structured study. If you already have your ticket and you need answers on the truck, on the ladder, or in the panel room, a fast searchable reference is going to save you real money in billable hours.

I built Ask BONBON because I was tired of flipping pages with dirty hands. The accuracy is there. The speed is there. But I'll keep running these tests quarterly and posting the results, wins and misses both. That's the only way to earn trust from guys who work for a living.