I'm a women's 7.5, I fluctuate from all sorts of sizes when it comes to UGG due to the way they fit and how they normally don't offer half sizes.
I based off my purchase off of others sharing their sizes (thank you so much to those who share!!) and the Big Kid's size 6 was a great fit for me. I love how I saved $40 and it's pretty much the same fit and product, I don't think the colorways even differ either from kids to adult Tasman. I don't have any issues with my foot not fitting securely inside the shoe, as I almost always wear socks with these Tasman's.
Great purchase, I gifted these for all my gf's too! Fantastic stocking stuffer

Im older- 50- and Ive never been a fan of this shoe brand since I have high arches and the boots used to hurt my feet after a time wearing- moreso-I never wear mule style shoes either since I cant keep them on my feet- but it was a christmas gift exchange list request so i purchased it for another person (a child). Unbeknownst to me- the parent bought the child a pair in the meantime so I ended up getting another gift thinking I would return these later but after being curious about the sizing- I goofed around with trying them on and just happening to be the same size as the person i bought them for-a child of all things but thought they looked big enough and they were, then I realized- I LOVED them and have worn them almost daily. Comfy , dont hurt my arches/plantar fasciitus and even better- they stay on- wild but I think I may have to be a fan now!

These are so cute and comfortable! My daughter had been asking for a pair for a very very long time! I had originally bout a size 2 because that is the size she is in any other shoe and fit perfectly but said they were a little tight. We returned and got a size 3 which has been perfect!!!!! She can wear them longer. She got chocolate milk on them but we were able to remove the spot with water and you can’t even tell! Definitely ordering more!!

As women sizing. These are NOT the same, they feel much stiffer and the lining is not stitched as thick as the adult style. I ordered a size 5 kids and 6 women’s. I was lucky enough to get my hands on both different times but randomly and did a side by side comparison. The kid size arrived before but as soon as I tried those on I immediately knew there was a different because my mom own these from 2 years ago. The quality of the slippers are thinner but I still prefer women sizing because it is much more comfortable and hugs the feet. The kids pair is cheaper BUT with that comes the quality.