Speed Distance Time Calculator
Solve kinematics speed equations using interactive formula triangles, unit converter matrices, and multi-leg route calculators.
km/h
🛣️ Route Journey Planner
Add dynamic steps to resolve cumulative splits.
| Leg | Distance (km) | Avg Speed (km/h) | Delete |
|---|---|---|---|
| #1 | |||
| #2 | |||
| TOTAL | 370.0 km | Overall Avg: 92.5 km/h | 04:00:00 |
SDT Formula Guide
The Kinematic Speed-Distance-Time trio maps the elementary equation of motion.
Clicking different quadrants of the interactive SVG triangle dynamically alters the calculated property:
- Speed (S): Computed as distance divided by elapsed time (d / t).
- Distance (D): Computed as traveling speed multiplied by traveling duration (S × t).
- Time (T): Computed as total distance divided by average velocity (d / S).
Common FAQs
What is the difference between speed and velocity?
How is average speed calculated for multiple legs?
Why do we include Mach conversions?
The Triangle Everyone Half-Remembers
s = d/t in real situations
Cover the one you want, multiply or divide the other two:
| Question | Formula | Example |
|---|---|---|
| How long will the trip take? | t = d ÷ s | Lahore–Islamabad, 375 km at 100 km/h ≈ 3 h 45 m |
| What speed do I need? | s = d ÷ t | 375 km in 3 h → 125 km/h (don't) |
| How far did I go? | d = s × t | 2.5 h at 80 km/h = 200 km |
| Pace ↔ speed (runners) | Invert | 6 min/km = 10 km/h |
| Average of a round trip | Total d ÷ total t | NOT the average of the two speeds |
The classic traps
Mixed units sink most answers: km with minutes, m/s with km/h (×3.6 converts) — normalize before calculating. The round-trip trap: drive out at 60 and back at 40, and the average is 48, not 50 — slower legs eat disproportionate time. And real trip planning needs moving speed vs overall speed: motorway averages collapse once city traffic, stops and tolls join the divisor.
Adjacent calculations
Unit gymnastics (mph ↔ km/h, knots, m/s) resolve in the unit converter; physics numericals that add acceleration outgrow this triangle and move to the scientific calculator; and journey durations across midnight or time zones sanity-check in the date difference calculator.