About this app
Calculate minimum pipe diameter in seconds. The DFU Pipe Sizing Calculator lets you tap to add fixtures — water closets, lavatories, showers, tubs — and instantly see the minimum drain pipe size per IPC Table 710.1. This is the tool you'll keep using after you pass the exam. 500+ PRACTICE QUESTIONS Covering drainage systems, DFU calculations, venting requirements, trap seals, water supply sizing, backflow prevention, gas piping (IFGC), and storm drainage. Every question includes a detailed explanation referencing the actual code section. COMPLETE CODE COVERAGE - IPC 2021 & IPC 2024 — International Plumbing Code - UPC 2021 — Uniform Plumbing Code (California & western states) PIPE SIZE REFERENCE Quick lookup tables for drain pipe sizing by DFU, vent pipe sizing by trap size, water supply sizing, and slope requirements. STUDY OFFLINE Every question and tool works without internet. Study on the job site, on the commute, or during downtime. PROGRESS TRACKING See your scores by category. Focus on weak areas. Know when you're ready to sit for the exam. SUBSCRIPTION INFORMATION Plumber Prep Pro Monthly: $3.99/month - Unlimited practice questions - Full pipe sizing calculator - All reference materials - Auto-renews monthly Payment will be charged to your Apple ID account. Subscription automatically renews unless canceled at least 24 hours before the end of the current period. Manage subscriptions in Settings > Apple ID > Subscriptions. Download now. Pass your plumber licensing exam the first time. Privacy Policy: https://www.voltexam.com/privacy Terms & Conditions: https://www.voltexam.com/terms Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Latest release
What’s New
Fresh look, same powerful tools. - Updated to VoltExam brand identity - Improved DFU calculator interface - Added monthly subscription option alongside lifetime purchase - Performance improvements
Audience growth
Ratings growth
Baseline captured. Growth appears after the crawler observes a changed rating count.
Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.
Price tracking
Price intelligence
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Sep 8, 2026 · 3:23 PM Free
Screenshots
