Voltage Drop Calculator. vs Knot Now

Perform accurate Voltage Drop and Wire Sizing calculations for both NEC® (National Electrical Code) and IEC standards. Built for electricians, engineers, and contractors who need reliable results on the go. Voltage Drop Calculator • Dual standards: Switch between NEC (AWG/Imperial) and IEC (mm²/Metric) • Enter voltage, current, run length, and power factor • Supports continuous load (125%), grouping, and ambient temperature corrections • Copper or Aluminum conductors for single-phase and three-phase systems • Detailed results including ampacity, derating, voltage drop, and load voltage • Automatic compliance checks (e.g., ≤ 3% for branch circuits) Wire Size Calculator (Reverse) • Calculates required wire size for a target voltage drop % • Suggests optimal AWG, kcmil, or mm² • Uses NEC Chapter 9, Table 9 (AC impedance) with DC fallback Professional Tools • Wire converter (AWG/kcmil ↔ mm²) • Generate and share PDF reports • Handy electrical formula cards • Localized in English, Spanish, French, German, Italian, Dutch, Portuguese, and Chinese

Knot Now is an offline field guide to 225 knots, animated in 3D, with step-by-step lessons you can follow at your own pace. BROWSE BY REAL-WORLD USE Knots are organized into camping, climbing, boating, fishing, rescue, arborist, pioneering, decorative, and rope care, plus a curated Essentials set of the eight knots worth learning first. Search by name, use, or classic reference number (ABoK). LEARN STEP BY STEP Every knot has a slow, scrubbable 3D animation you can rotate, zoom, and play back at 0.5x-2x speed, paired with plain-language steps. Jump a step at a time, or drag the timeline to any point in the tie. KNOW THE TRADEOFFS Each knot lists what it is good for, its strengths, and what to watch out for, plus a one-tap comparison against a similar alternative for when two knots do almost the same job. CAST TO A BIGGER SCREEN Send any lesson to a nearby TV or Mac over AirPlay. The lesson video is generated on your device — nothing is uploaded anywhere. TRACK YOUR OWN PROGRESS Mark knots as favorites, add them to a practice list, or mark them mastered, and keep field notes on any knot. Everything stays on your device. Knot Now works fully offline. No account, no sign-in, and no network connection required. For any knot used in climbing, rescue, arborist work, or another life-safety context, verify the finished knot and technique with a qualified instructor. The animations are a learning aid, not a substitute for training.