WireSizer vs DC Wire Sizer

WireSizer is the fast, accurate, and easy-to-use DC wire size calculator for choosing the correct wire gauge every time. Simply select your DC voltage, current, and total circuit length with flips of your finger. No keyboard required. WireSizer instantly calculates the correct wire gauge for the Voltage Drop percentage you need. WireSizer is ideal for: • Boats and marine electrical systems • RVs, trucks, and cars • Radios and electronics • Solar power and battery-based DC systems • Any low-voltage DC system up to 60 VDC Suitable for both professionals and DIY users. WireSizer automatically calculates the minimum wire size required for your circuit (assuming copper wire), taking Voltage Drop into account for installation and temperature conditions. Results are checked against current-carrying capacity (ampacity) limits to prevent using unsafe undersized wire. Supported values: • Voltage up to 60 VDC • Current up to 500 amps • Total circuit length up to 600 feet or 200 meters • Voltage Drop 1 to 20 percent • AWG wire 18 gauge to 4/0, plus 250 & 300 kcmil • SAE wire 18 gauge to 4/0 • Metric wire 0.75 mm² to 150 mm² WireSizer allows you to fine-tune calculations based on real-world installation conditions: • Engine compartment or other high-temperature environments • Sheathed, bundled, or conduit-run wire • Wire insulation ratings from 60°C to 200°C WireSizer also includes a Materials List so you can record and review all of your wire selections in one place. WireSizer calculates DC wire sizes in accordance with ABYC E-11 (July 2025). For typical low-voltage DC circuits, results generally correspond with ISO 13297:2020. Results are a design aid; final wire selection and installation compliance remain the installer's responsibility. Number and decimal formatting will follow your device's regional and language settings. WireSizer works without an internet connection and contains no ads. Designed exclusively for DC circuits - not for use with AC circuits. Results are a design aid. Final wire selection and installation compliance remain the installer's responsibility. WireSizer will cost you less than the wire scraps you probably throw away at the end of the day.

Adding accessories (bilge pumps, electronics, solar, etc.) or upgrading batteries (AGM, Li, etc.) this year?  The #1 Cause of Boat and RV fires is DC wiring!  Undersized wires can damage equipment or cause fires.  The top-rated DC Wire Sizer calculates wire size for any DC voltage (ideal for solar in series). Plus lets you SAVE, EDIT, SUM, EMAIL and EXPORT the wire runs and material for your electrical plan, wire purchases, work orders, and records. And the Sizer Wizard option makes wire sizing easy for EVERYONE! Fast and safe wire sizing calculator for your next DC wiring project (battery, charger, inverter, trolling motor, stereo, and more). Designed with and for Marine Electronics Installers, Repair Services, Boat Builders, Surveyors, Do-It-Yourselfers, and Boat Owners. ONLY DC WIRE SIZER OFFERS these FEATURES: - Select any DC voltage and up to 500 amps - Results display wire size, VOLTAGE DROP (VD), and AMPACITY! - More granular “What if” analysis of ampacity & VD based on wire sizes & length - Choose from three methods of entering wire lengths for fast entry including separate positive/negative wire lengths (when different or negative is contact grounded, like a starter) - SAVE Wire Runs with the option to select or enter Wire Run & Project Name, wire type, wire color, status, and material source (Inventory or Buy) - EDIT Wire Runs including wire length, amps/watts, max voltage drop, insulations, inside/outside engine room, bundle, and the fields above. - SUMs active wire run lengths by size, type, and color to make purchasing easier and less expensive when by the reel (25’, 50’, 100’, etc.) - Select from a wire type list (e.g., primary, battery, safety, flat, duplex, triplex, mast, twisted, bilge, trailer, and solar cable) - Select marine standards (ABYC or ISO) - Change Unit of Measurement (Feet or Meters) in existing Wire Runs - Easy to use Sizer Wizard - Email and Export of Wire Runs and Raw Material MORE FEATURES: - Set default Wire Gauge (AWG, SAE, or MM2) - Set default Unit of Measure (feet or meters) - Select or enter Maximum Voltage Drop % - Select Bundle Size (1, 2-3, 4-6, 7-24, and 25+) - Select Insulation rating (60°, 75°, 80°, 90°, 105°, 125°, and 200°C) - Tap Inside/Outside Engine Room - Spin Amp/Watts and Wire Length for fast entry - Built-in Help and Technical Reference includes installation tips, connector types, color codes, tables (Voltage Drop, Ampacity, & Bundle), formulas (Power Triangle, Ohm's Law, etc.), recommended tools/books, and more. HERE’S WHAT REVIEWERS ARE SAYING: "The DC Wire Sizer is the most complete and comprehensive marine DC wire-sizing tool available. Developed for both marine professionals (the Wire Sizer Pro) and the occasional tinkerer (the Wire Sizer Wizard), the app determines the proper wire size, along with the voltage drop and ampacity by using the ABYC E-11 or ISO 10133 formulas and tables.” -  OnboardOnline (2013) "Stay organized by adding a wire description to the wire run and assign it to a project name (ie boat name, owner or work order). Mark the wire run as "Complete" or “Cancelled”, re-order wire runs within a project or move them between projects. Tired of adding wire runs in order to figure out what to purchase and how much? DC Wire Sizer sums the active wire runs for you by wire size (e.g. 8 AWG) and type (e.g. Safety Duplex, Battery Cable, and Primary Wire).” - marinabusiness (AU 2013) "If you're doing a lot of wiring on your boat, the app allows you to save the calculations with project names and wire type.  The app then can sum the length of the wire runs by wire type and size which can be used as a shopping list for your projects.  No other app offers these unique features and that's what makes it a winner.”  - i-marineapps (2013) "This is the best wire sizer program I have seen to date.  I can size and make a list at the same time also there is a better selection of amps and volts.” - Keith Herridge, Special Projects, Lyman-Morse Boatbuilding