How the planner decides
Every result is built from published figures, not estimates. The METRORail Red Line is the spine: it stops at Stadium Park/Astrodome, a short walk from the gates, and runs every 6 to 12 minutes on matchdays at a $1.25 fare. From the airports, METRO Route 500 Downtown Direct connects IAH and Hobby to downtown for $4.50, roughly every 30 minutes between about 5 AM and 9 PM, where you transfer to the Red Line. Driving in from outside the core, the Fannin South Park & Ride is $25 with round-trip rail included, and the West Loop Transit Center offers free parking with a $2 connecting bus.
Driving all the way to NRG is the option the tool will rarely recommend. Official match parking is $98.99 to $174.99 per vehicle per match, the host committee has said there will be fewer spaces than a normal Texans game, and the post-match lot exit adds 45 to 90 minutes. The math almost always favors rail.
The heat note is the part visitors underestimate. Inside the stadium the roof stays closed and the interior is held near 72°F, but 6 of the 7 Houston matches kick off at noon, when the street outside runs near triple digits. The route you pick decides how much of that you stand in. The least-exposure path is almost always rail, because the train is air-conditioned and the Stadium Park/Astrodome walk is short.
Plan the rest of your trip with the Houston matchday hub, the full getting-around guide, and where to stay for a base on the Red Line.