Two calculators, one cross-checked number
A 5:00 min/km pace converts to a speed of 12 km/h, according to the pace converter — which also reports that same pace as 7.46 mph internally. Taking that real 12 km/h figure and running it through the entirely separate speed converter, converting km/h to mph, gives 7.456454 — matching the pace converter's own 7.46 mph result once rounded to 2 decimal places.
Why these two independent calculations agree
The pace converter computes its own km/h-to-mph conversion internally, using the same 1.609344 km-per-mile constant that the dedicated speed converter uses via its shared unit registry. Two different pieces of code, built for different purposes, land on the identical constant — which is exactly why converting the same real speed value through either one gives the same answer.
Why this consistency check matters
If the pace converter used a slightly different or outdated mile conversion factor than the dedicated speed converter, this cross-check would reveal a real discrepancy between the two — instead, running the same real number through both confirms they're using a consistent definition of a mile.
A practical use for chaining pace into speed conversion
Someone training with a pace-based plan (minutes per km) but needing a speed figure for a treadmill calibrated in a different unit (like ft/s or knots, not covered by the pace converter's own mph/km-h outputs) can take the pace converter's km/h result and continue the conversion through the speed converter — the two tools compose cleanly because they agree on the underlying numbers.