Make the distance familiar
A 1,000 km length contains 10,000 straight 100 m sections. Picture a marked 100 m sprint straight repeated end to end, rather than a whole stadium lap.
Work it out, one step at a time
Turn kilometres into metres
1,000 × 1,000 = 1,000,000 m
One kilometre contains 1,000 metres. The length stays the same.
Choose a speed, then find the time
1,000 km ÷ 100 km/h = 10 h
At a chosen constant 100 km/h, it takes about 10 hours. This is a calculation with no stops; hills, traffic and real journey conditions are not included.
What if the speed doubles?
For the same distance and constant speed, time halves. For example, 10 km takes 2 hours at 5 km/h but 1 hour at 10 km/h.
The distance is this page’s chosen input. The speed is a teaching assumption. Time = distance ÷ speed.
Build a scale modelChoose two references and change the model size.
Build a scale model of any two lengths
Choose from all 71 Macro and 54 Micro references, or enter your own length. Set B’s model length and see A change on the same fixed metre ruler. The bars represent the stated lengths, including their different measurement definitions.
- Length ratio A / B
- Model length B
- Calculated model length A
A · Chosen distance A
1,000 km
A chosen input length, not a new measurement of a reference.
User / page input
The ratio follows this input assumption.
Definition and evidence reviewOriginal sourceB · Earth radius
6,371 km
Volumetric mean radius, rounded from JPL’s 6,371.0084 km to the existing 6,371 km comparison.
Source claim checked
Equivalent-volume sphere; flattening, terrain and local radius differ.
Definition and evidence reviewOriginal sourcemodel A = (A / B) × model B
This calculator uses the existing journey comparison inputs. Review-pending or conceptual entries remain illustrative inputs here; the public reviewed dataset keeps their numeric values withheld. Radius, height, diameter and experimental bound keep their individual definitions.
Latency and transfer duration measure different things
For a known 1,000 km propagation path in vacuum, light takes d/c = 3.336 milliseconds one way; an immediate return takes 6.671 ms. The exact vacuum speed is 299,792.458 km/s. This gives an ideal propagation baseline. Network path length, transmission medium and device processing define an actual connection's delay.
Now assume a clean link sending a 100 Mbit message at 100 Mbit/s, with vacuum propagation and no protocol or processing overhead. Putting all the bits onto the link takes message size / rate = 1 second. The first bit arrives after about 3.336 ms; the final bit arrives after about 1.003336 seconds from the start. Mbit means megabits here, distinct from megabytes.
A faster link changes only part of this model
Doubling the assumed rate to 200 Mbit/s reduces serialization to 0.5 s and final-bit arrival to about 0.503336 s. Propagation across the same 1,000 km remains 3.336 ms. Distance controls propagation; message size and bitrate control serialization. Keep these quantities separate when comparing a quick response with a large download.
Closest ScaleTrip references
Page distance: 1,000 km
- Great BritainReference measurement: Length · 970 km
Ratio (page distance ÷ reference): ≈ 1.03×The north-to-south extent of Great Britain.
- Korean PeninsulaReference measurement: Length · 1,100 km
Ratio (page distance ÷ reference): ≈ 0.91×The north-to-south extent from near Mount Paektu to the southern coast.
- Los Angeles–San FranciscoReference measurement: Distance · 560 km
Ratio (page distance ÷ reference): ≈ 1.79×The distance between Los Angeles and San Francisco.
Sources for these values
- NIST — Definitions of SI base units — exact vacuum speed of light used for the ideal propagation calculation; message size and bitrate are teaching assumptions · calculation verified from source value 2026-10-13