DMS ↔ Decimal Converter
High-precision geographic coordinate transformation. Live bidirectional conversion with 5-decimal place accuracy.
About the DMS to Decimal Degrees Converter
The DMS to Decimal Degrees Converter is a fast, accurate, and completely client-side web utility designed to perform live bidirectional conversion between Degrees-Minutes-Seconds (DMS) and Decimal Degrees formats with industry-standard precision.
Built for surveyors, GIS professionals, navigators, cartographers, engineers, and outdoor enthusiasts, this tool eliminates the hassle of manual calculations and reduces the risk of conversion errors. It supports a wide variety of real-world input formats, handles negative coordinates and directional indicators (N/S/E/W), and always delivers results to exactly five decimal places in Decimal Degrees.
All processing happens locally in your browser — no data is ever sent to a server, no accounts are required, and the tool works fully offline after the initial page load. This privacy-first approach makes it suitable even for sensitive or professional coordinate work where data confidentiality matters.
The converter follows standard mathematical formulas: Decimal Degrees = Degrees + (Minutes ÷ 60) + (Seconds ÷ 3600), with precise reverse conversion and careful handling of rounding to maintain accuracy. Whether you work with traditional maps, GPS devices, GIS software, or field notes, this utility provides instant, reliable results that you can trust.
Our goal is simple: deliver a clean, lightweight, and highly precise coordinate conversion experience without unnecessary features or tracking.
How to Use
- 1 Enter your coordinates in the DMS field using any common format. Examples include 40° 26' 46.5", 40 26 46.5 N, or -73 56 59.87.
- 2 As you type, the Decimal Degrees field updates instantly with the result rounded to exactly five decimal places.
- 3 Alternatively, type a decimal value (positive or negative) in the bottom field to see the equivalent DMS format appear immediately, with seconds shown to two decimal places.
- 4 Use the copy buttons next to each field to quickly copy the result to your clipboard for use in reports, GIS software, or field notes.
Frequently Asked Questions
Is the converter completely offline?
Yes. Once the page loads, all calculations run locally in your browser. No internet connection is required after the initial load, and no data is ever sent to any server.
What level of precision does it provide?
Decimal Degrees are always shown to exactly five decimal places, providing roughly one-meter accuracy at the equator. Seconds in DMS format are displayed to two decimal places for equivalent precision.
Does it support negative coordinates and directions?
Yes. The converter correctly handles negative values and direction letters (N, S, E, W). You can enter coordinates with a leading minus sign or with directional indicators.
What input formats are supported?
The tool accepts most common DMS formats including symbols (° ' "), space-separated numbers, decimal seconds, and mixed styles. It automatically normalizes the input for reliable conversion.
Is my data private?
Completely. This is a stateless client-side application. No coordinates or usage data are collected, stored, or transmitted.
Can I use it for professional surveying or GIS work?
Yes. Many professionals use it for quick conversions and verification. However, always independently verify results for legally binding or high-stakes projects.