The Nell Ueno Okachimachi in Tokyo

Very accommodating and friendly staff. Great service and clean amenities. Bedding and room is clean. Capsule space is cozy. I am 189cm tall and just fit in the capsule but was fine to sleep in. Staff have limited English but Google translate made communicating easy. Great location to have somewhere to rest after exploring all day. Would stay again

Cheap, clean and convenient, starts around 4k yen per night, you can also just take a break and shower here (japanese sentou)
toothbrush, shaver, robe and towel available if you sleepover.
there is also cafetarian with drink vending machine, free wifi, microwave, and charging slot for your smartphone

This men-only capsule hotel near JR Ueno Station features a smooth flow from entry to sleep. It has a clean, stylish appearance and is available from 4,000 yen per night. After checking in, guests can leave their luggage in the locker room and enjoy a spacious bathtub and a variety of amenities in the bathroom. The bedrooms feature a retro-futuristic design with capsules arranged in a row. New mattresses and pillows provide a comfortable sleep and an excellent time-performance accommodation experience.

Very modern and comfortable capaule hotel. Extremely friendly staff who are decent at speaking English. Beds are decently comfy, pillows are very nice. Whole hotel is very clean. One smoking room next to a small-medium sized lounge with a couple vending machines, a tv, a microwave and a hot tea water dispenser. Downstairs by the bath is a free machine that dispenses coffee, water, lemon water, green tea and barley tea. All have the option of hot or cold and all are unlimited and free. Bath is very nice, only complaint is it was a little too hot. Sitting a little above 40°C was too hot to stay in for long. All in all very nice hotel, would recommend.