Have done BKK-NRT-XXX many times -- there will not be an issue. They will be able to check your bag all the way though and print your BP for your NRT-DEN flight when you check in. If for some strange reason they can't the transfer desk at the bottom of the stairs you will see after clearing security. 3:30pm is peak arrival / departure time for the US bank of flights -- but NRT transfer security is pretty efficient and you shouldn't have any issues at all with this connection. In fact -- if for some reason the flight does get delayed coming in they will often meet the connecting passengers as you deplane (they usually are holding signs for your flight -- and sometimes have even set up a desk) and then personally escort you through priority security. NRT is one of the best airports in the world for connections -- try not to worry about it and enjoy BKK!

Sounds great, thanks!

Are overnight layovers for flights for ANA J flights (SFO-NRT) normal? I'm only given the option of booking YVR-SFO-NRT, where YVR-SFO is overnight. Wondering if its worth it for a J seat or if I should cancel and wait for something better.

You should be able to catch the 7am United flight, or 8:30am Air Canada flight. But if you are looking for awards, they may be scarce on the morning flights.

I was able to find a SFO->NRT sometime after my last post, not sure why it wasn't showing at first through the award search.

I will be arriving at HND in super early morning (5:00 AM), wondering if the airport has any locker for checked bags so that I can travel Tokyo without carrying the bags?

Are you staying in Japan? Most hotels will keep your bags until check-in, which is usually from 3:00 PM.

I'm not staying in Japan, it's a 13 hour layover, so I figured I should probably visit the city a bit.

If your two flights are on the same ticket (same PNR) then you should be able to check bags all the way through to your final destination.
If you're travelling on two separate tickets and you have to collect your checked bags on arrival at HND, you could store them in a locker:
https://tokyo-haneda.com/en/service/...in_locker.html

The site above says that the lockers are 400 yen or 600 yen per 24 hours. In fact, I think the charge is actually for a calendar day, rather than for a 24 hour period, but since you won't be staying past midnight it's a moot point.

Thanks a ton! This is exatly what I'm looking for! My flights are on the same ticket, but folks said for air canada flight it is most likely I need to recheck my bag, so I guess I would just plan ahead to avoid any surprises.

What airline do you use to depart from HND?

I'll be arriving at Haneda Airport via All Nippon Airways, then departing via Air Canada flight.

ANA has no problem checking your luggage through on a connection like that. With the caveat that if you are on separate tickets and your Air Canada ticket is without luggage allowance they might decline to do so.

1) DFW-NRT-HKG The connection time is 23 hours.
Do I need to recheck my bags?
Do I have to leave the airport?
Can I hang out at the airside and get my bags later?
Where are the baggage storage lockers?

Best,
Michael

As Narita closes overnight, you will need to enter Japan and overnight in a hotel.
Your airline should be able to check the bags through and not have need to reclaim them.
No, you can't proceed airside after arrival, but will need to enter Japan.