ETA Calculator
Calculate your estimated time of arrival from current position, distance remaining, and speed.
Works for driving, sailing, hiking, and flying.
The ETA (Estimated Time of Arrival) is one of the most fundamental navigation calculations. It answers the question every traveller asks: “When will I get there?”
The core formula is: Time = Distance / Speed
Then: ETA = Departure time + Travel time
While simple in principle, accurate ETA requires accounting for several real-world factors:
Speed variability: Average speed over a journey is rarely constant. Driving involves traffic, stops, and varying speed limits. Sailing involves wind changes and tacking. Hiking involves elevation gain and terrain.
Stops and rest breaks: For road trips, add 15–20 minutes per 2 hours of driving. For sailing passages, account for watch changes and meal stops. For long-distance hiking, apply the Naismith Rule (which adjusts for elevation).
Common average speeds for planning:
- Highway driving: 100–120 km/h (60–75 mph)
- City driving: 30–50 km/h (20–30 mph)
- Cycling (road): 20–30 km/h (12–18 mph)
- Sailing: 5–8 knots (9–15 km/h)
- Hiking (flat): 4–5 km/h (2.5–3 mph)
- Commercial flight (cruise): 850–900 km/h (530–560 mph)
- Walking: 4–5 km/h (2.5–3 mph)
Dead reckoning: When GPS is unavailable, ETA is calculated from last known position, logged speed, heading, and elapsed time. This is standard practice in marine and aviation navigation.
This calculator optionally takes a departure time and returns an actual clock time arrival, which is more useful than a raw duration for real journey planning.