Speed Converter

How to Use

1. 1Type a number in the input field at the top
2. 2Select your starting unit from the From dropdown (e.g. Kilometer per Hour, Mile per Hour, Knot)
3. 3Select your target unit from the To dropdown - the result appears instantly
4. 4All conversions appear simultaneously, grouped by system: Metric, Imperial/US, Nautical, and Scientific & Reference
5. 5Hover any result row to reveal the copy and swap buttons
6. 6Click the copy icon to copy a value to your clipboard
7. 7Click the swap icon (⇅) on any row to use that unit as the new input and reverse the conversion
8. 8Adjust 'Sig. figures' to control result precision (3 to 12 significant digits)
9. 9Toggle 'Sci notation' to display very large values like the speed of light in exponential form
10. 10Collapse a unit group by clicking its header to reduce clutter
11. 11Open 'Common conversions' at the bottom for a quick reference table

Features

• 22 speed units across 4 unit systems
• Metric: millimeter/s, centimeter/s, meter/s, meter/min, meter/h, km/h, km/min, km/s
• Imperial/US: inch/s, inch/min, foot/s, foot/min, mph, mile/min, mile/s
• Nautical: knot, nautical mile/min, nautical mile/day
• Scientific & Reference: Mach 1 (ISA sea level), speed of sound in water, Earth orbital speed, speed of light
• All conversions shown simultaneously - no need to pick a single 'to' unit
• Click any result row to use it as the new input (instant reverse conversion)
• Adjustable significant figures: 3, 4, 5, 6, 8, 10, or 12 digits
• Toggleable scientific notation for very large values (speed of light)
• Collapsible unit-system groups to reduce visual clutter
• One-click copy to clipboard for any converted value
• Common conversions quick-reference table (km/h ↔ mph ↔ knots ↔ Mach)
• 100% browser-based - no server, no data upload

Frequently Asked Questions