No, but it will tell you if flights are available for RUC upgrades when logged in (as shown below). Since it's just based on Z bucket availability as noted in Wiki, if you familiarize yourself with the Z fares on a route, you can use Google Flights to figure out which dates have flights with availability based simply on fare pricing.




After checking FC fares on DTW-LAX, I verified Z fares range from $684 (with 30 day advance purchase) to $989 (with no advance purchase). So any date below showing fares between $684 to $989 has at least one flight with Z bucket open which is RUC eligible. Any dates with pricing higher than $989 will only have I, D, C, or J fares available which means there is no Z bucket open on any flights on that date.