Get the right wire size in seconds. Spin the wheels, read the gauge. No keyboard or internet needed. Ad-free. ABYC E-11 compliant up to 60 VDC. Trusted since 2012.
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.
I use this app all the time! Would use it even more if it could support higher voltages. I’d like to see at least 150vdc, and 240vac. Thanks for the useful tool!
Developer Response
The latest version now allows voltage up to 60 volts DC. Calculating wire sizes for higher voltages requires taking into account some additional factors to do properly (which many voltage drop calculators neglect). We are planning on investigating the feasibility of this in the future. Thanks for the review!
Simple, ABYC-based and by far the best
LaughingSailor
It’s so nice having a professional app that does its job and does not get bogged down with bells and whistles: The app only has one page! I have used WireSizer daily for years because it’s quick and gives the critical voltage drop information needed to choose correct wire size, while being entirely interactive: Spin gauge, amperage or length wheels and the results are instantly updated, making decisions easy and quick.
Easy to use and accurate
24Spokes
I am a Marine Engineer and I use this app at my desk and in the field to run “how to” calculations to determine the wire size required for a particular voltage, load current and circuit run. The spinner wheels make it very easy to enter the data and the drill down that is available when the results tapped is an excellent bonus. My favorite wire sizing app.
Works well, some limitations
solar installs
Overall it’s a very good tool. I use it to size DC wires runs for solar. I have verified accuracy with manual calculations of voltage drop. It’s limited to 50vdc maximum so works well for up to 48vdc battery banks but can’t use it for solar panels in series as voltage exceed 50v limit.
Developer Response
The latest version of WireSizer now supports up to 60 VDC. Suitable for charging systems (and solar) for 48vdc battery systems. Thanks for the review!
+ Performance, User Interface, and Stability improvements.
+ Added 250 kcmil and 300 kcmil wire gauges.
If you have any questions, problems, or comments, please contact us at support@WireSizer.com!
Version 3.34
The developer, Juggernaut Technology, Inc., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
Juggernaut Technology, Inc.
Size
2.4 MB
Category
Utilities
Compatibility
Requires iOS 26.0 or later.
iPhone Requires iOS 26.0 or later.
iPad Requires iPadOS 26.0 or later.
Mac Requires macOS 14.0.0 or later and a Mac with Apple M1 chip or later.
