🌍 Degrees Minutes Seconds ↔ Decimal Converter
Convert between DMS (40° 26' 46") and Decimal Degrees (40.446°)
Separate with spaces. Symbols (° ' ") are optional. Supports decimal seconds.
✓ Valid input examples:
40 26 46 → 40° 26' 46"
40° 26' 46.8" → with decimal seconds
-33 51 54 → negative (South/West)
30' → 0° 30' 0"
100 5" → 100° 0' 5"
Enter a decimal number. Use negative for South/West.
✓ Valid input examples:
40.446111 → 40° 26' 46"
-33.8650 → 33° 51' 54" S
0.5 → 0° 30' 0"
-122.4194 → 122° 25' 9.84" W
Conversion Formulas
📐 DMS to Decimal
DD = D + M/60 + S/3600
Example: 40° 26' 46" = 40 + 26/60 + 46/3600 = 40.4461°
📐 Decimal to DMS
D = int(DD)
M = int((DD - D) × 60)
S = ((DD - D) × 60 - M) × 60
M = int((DD - D) × 60)
S = ((DD - D) × 60 - M) × 60
Example: 40.4461° → 40° + 0.4461×60 = 40° 26' 46"
Understanding Coordinates
🌐 DMS Format
Degrees° Minutes' Seconds". Traditional format. Each degree = 60 minutes. Each minute = 60 seconds. Example: 40° 26' 46.8" N
🔢 Decimal Degrees
Single decimal number. Modern GPS format. Easier for calculations. Negative = South/West. Example: 40.446889
🧭 N/S/E/W
North and East are positive. South and West are negative. Latitude: -90° to +90°. Longitude: -180° to +180°.
📍 Precision
1 second ≈ 31 meters at equator. 0.0001° ≈ 11 meters. GPS typically ±3-5m accuracy. More decimals = more precision.
Frequently Asked Questions
How do I convert degrees minutes seconds to decimal?
Formula: Decimal = Degrees + Minutes/60 + Seconds/3600. Example:
40° 26' 46" = 40 + (26÷60) + (46÷3600) = 40.446111°
How do I convert decimal degrees to DMS?
Steps: 1) Degrees = integer part. 2) Multiply decimal by 60 →
integer = minutes. 3) Multiply remainder by 60 → seconds. Example: 40.446111 → 40° 26' 46"
What is the DMS format?
Degrees Minutes Seconds. Written as 40° 26' 46" (40 degrees, 26
minutes, 46 seconds). Traditional format for geographic coordinates. Each degree = 60', each minute =
60".
What are decimal degrees?
Single number with decimals representing position. Example:
40.446111. Used by GPS devices and mapping APIs. Easier for calculations than DMS.
How do I handle negative coordinates?
South latitudes and West longitudes are negative.
33° 51' S = -33.85°. 122° 25' W = -122.4167°. Keep the sign through calculation.
What is the precision of coordinates?
1 degree ≈ 111 km. 1 minute ≈ 1.85 km. 1
second ≈ 31 m. 0.0001° ≈ 11 m. 6 decimal places = ~11 cm precision.
How do I enter coordinates without symbols?
Just separate with spaces: "40 26 46" means 40° 26' 46". Our
converter parses numbers automatically. Symbols are optional.
Can I use decimal seconds?
Yes! Enter "40 26 46.8" for 40° 26' 46.8". Decimal seconds provide
sub-second precision. Result will show full decimal precision.
What if I only have minutes?
Enter with ' symbol: "30'" = 0° 30' 0" = 0.5°. Or enter as "0 30
0". Partial input is supported.
How accurate is GPS in meters?
Consumer GPS: ±3-5 meters. Differential GPS: ±1
meter. RTK GPS: ±2 centimeters. Coordinate precision should match device accuracy.
What's the difference between latitude and longitude?
Latitude: North-South position (-90° to +90°).
Longitude: East-West position (-180° to +180°). Format: (lat, lon) or "40.446, -79.982"
Why use decimal degrees over DMS?
Decimal is easier for: calculations, databases, programming.
DMS is better for: human reading, traditional maps, surveying. Both are equally valid.
How do I convert coordinates for Google Maps?
Google Maps uses decimal degrees. Just paste "40.446111,
-79.982222" into search. Or convert DMS first. Click any point → coordinates appear.
What is a minute of latitude?
1 nautical mile = 1.852 km. At any latitude, 1' of latitude ≈
1.852 km. This is why nautical miles are useful for navigation.
Can coordinates have more than 6 decimal places?
Yes, but usually unnecessary. 6 decimals = ~11 cm precision. 8
decimals = ~1 mm. GPS accuracy is typically ±meters, so 6 decimals is sufficient.
How do I convert UTM to DMS?
UTM (Universal Transverse Mercator) uses meters, not degrees.
Requires specialized conversion considering zone and hemisphere. Use a UTM converter tool.
How accurate is this converter?
Uses JavaScript floating-point math. Results accurate to ~15
significant digits. More than sufficient for any GPS or mapping application.