I failed the TDLR Calculations part. What should I study first?
Start with your score report, not a textbook. The Calculations part is scored on its own now, so the report tells you which calc families cost you. Drill your bottom two first: usually some mix of conduit fill, box fill, dwelling load, and motors. Fix those before touching anything you already passed.
Last reviewed June 2026 · Answered by JourneymanIQ staff
Read the report before you study
The TDLR report breaks the Calculations part down. The two lowest lines are your whole plan. Do not re-study the lines you already cleared. That is wasted time you do not have before a retake.
Drill one calc type at a time
Pick the lowest one and work it until the setup is automatic. A clean five-step setup beats memorizing formulas. Conduit fill, box fill, dwelling load, and motors are the usual point-leakers, and each has its own room here.
Build speed last
Once the setup is solid, time yourself. The Calculations part is 26 questions in 110 minutes. If a problem takes more than four minutes on a clock, that is a pacing problem to fix before test day, not a knowledge problem.
Bottom two topics, clean setup, then speed. That order is how most retakers turn a fail into a pass.
Sources
Practice questions and explanations on JourneymanIQ are original. We paraphrase the NEC and cite article numbers, and we do not reproduce NEC text or real exam questions.
Find your weak topics before test day
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