Your total trip with all stops is around 770 miles / 1240 km, taking roughly 14.5 hours for the whole trip. If you want to see every small town along the way, you can get a full list of cities between UUD and COQ.
Start from Ulan-Ude Airport.
Darkhan, Mongolia is stopping point #1 after driving about 350 km (220 miles) or 4 hours.
Ulaanbaatar, Mongolia is stopping point #2 after driving about 220 km (140 miles) or 2.5 hours. Your total trip so far is about 570 km or 360 miles over roughly 6.5 hours of driving.
Finally, Choibalsan Airport is your destination after driving about 670 km (420 miles) or 8 hours. Your total trip with all stops is around 1240 km or 770 miles, taking roughly 14.5 hours for the whole trip.
Travelmath helps you figure out where to stop when planning a long road trip from one location to another. The best stopping point for an overnight hotel stay or a break from driving often depends on how far or how long you want to drive before pausing to rest. You can find the closest city to your stopping point to look for hotels, or explore other cities and towns along the route. Use this as a road trip planner when you're driving cross-country or mapping a route with multiple stops.