Hydro Flask bottles are extremely popular and high-quality vacuum insulated stainless steel bottles. However they are quite thick so you might be wondering whether or not Hydro Flask bottles fit in cup holders.
The 12-24 oz Hydro Flasks fit in all but the smallest car cup holders. They have a diameter of 2.87-2.91 inches (7.23-7.39 cm) and most car cup holders are 3 inches or more. The 32 oz and 40 oz Hydro Flasks do NOT fit in car cup holders and require a car cup holder adapter in order to fit.
Once you get to the 32 oz size and larger the bottles become extremely thick at 3.58 inches and higher and will not fit in any standard cup holders.
Important Size Considerations
There are a couple of size considerations you need to think about depending on what Hydro Flask bottle you have.
Below are the diameters of the most popular Hydro Flask bottles you'll be looking to fit in cup holders:
Standard Mouth: 2.87 inches (7.23 cm)
Wide Mouth: 2.91 inches (7.39 cm)
32+40 oz Wide Mouth: 3.58 inches (9.09 cm)
You'll need to measure your cup holder to see whether or not it's going to be big enough to fit the Hydro Flask you choose.
While the difference in thickness between the Standard Mouth and the Wide Mouth is super small, it can actually make a big difference as to whether or not your bottle will fit in a cup holder.
I Tested My Hydro Flask In A Few Different Cup Holders
I have a compact car as well as a camper van, each of which had a couple of different cup holders I could test my Hydro Flask in.
It's important to not that I have the thinnest Hydro Flask bottle available. Click here to see the full Hydro Flask Sizes Chart and Guide for details and sizing on all the different bottles.
Below you can see the result:
Small Car Front Cup Holder
Both my Hydro Flask bottles only JUST squeezed into the front of my small car cup holder.
The top of the cup holder is wider than the bottle so about half way down it got stuck and wouldn't go any further. But it still fit firmly enough that it is unlikely to fall out when I'm driving.
You can see my 10-12 oz takeaway coffee cup next to it which is much thinner and fits in my cup holder much easier.
The coffee cup obviously doesn't have the thick vacuum sealed insulation like the Hydro Flask bottle.
Small Car Back Cup Holder
At the back of my small car is another cup holder.
This cup holder is just a tiny bit smaller than the cup holder in the front of my car but that small difference means that my Hydro Flask wasn't able to fit at all.
After Market Cup Holder #1
My campervan didn't come with cup holders so I've installed 2 different types myself which I was able to test out.
One has this broken upper ring to hold onto your bottle/cup and a square base for it to sit in.
I had to stretch the upper ring arms a little to get the bottle in but then it fit nice and easily.
After Market Cup Holder #2
You couldn't get a more snug fit if you tried. This cup holder had the EXACT diameter as the Hydro Flask.
It was such a tight fit that I had to remove the cardboard sleeve off my Hydro Flask otherwise it wouldn't fit. It was also so tight that the Hydro Flask rubbed a bit on it's way in and out. I do worry that if I was to do this a lot if might start to make marks on the paint of my Hydro Flask.
Here you can see the difference between the Standard Mouth and Wide Mouth width.
The Wide Mouth is just a tiny bit wider in diameter and this means it was NOT able to fit in this cup holder.
Large Car Front Cup Holder
My girlfriend came and picked me up for lunch and she has a larger car than me so I tried my Hydro Flask in her car.
It easily fit in her front cup holder with room to spare. The slightly wider Wide Mouth bottles would have easily fit in here too.
Large Car Back Cup Holder
The cup holder in the back of her car was a different story. My Hydro Flask only just wedged in and got stuck about half way.
Still good enough that it wouldn't fall out but similar situation to the front cup holder in my small car.
Large Car Door Cup Holder
She also had a cup holder in the door so I tested it out for good measure and it fit just fine.
The Wide Mouth Hydro Flask Did NOT Fit In Some Cup Holders
As you can see in almost every cup holder I tested my Hydro Flask Standard Mouth bottle only JUST fit and in one in particular the Wide Mouth cup holder didn't fit.
While 0.04 inches (0.16 cm) is not a huge difference on paper, in fact it's hardly noticeable at all, it would actually make all the difference for me as to whether or not I could fit my Hydro Flask in my main cup holder in my campervan.
Do 32 oz and 40 oz Hydro Flasks Fit in Cup Holders?
The answer to this question is a resounding no! 32 + 40 oz Hydro Flasks are much wider than smaller sizes and won't fit into any standard sized cup holder.
I don't personally have a 32 oz but my work colleague does and her's is much thicker than my 18 oz bottle and wouldn't fit into any of the cup holders shown above.
The width of a 32 oz or 40 oz Hydro Flask is 3.38″ (9.09cm) which is 0.71 inches (1.8 cm) wider than a standard mouth Hydro Flask. This is a fair amount bigger and no cup holders are really designed to fit something this large.
If you want to fit one of these large bottles into a cup holder then you'll need a cup holder expander:
Hydro Flask Cup Holder Expander
If your Hydro Flask does not fit in your cup holders then don't worry, you don't have to settle for a life where you just can't use your cup holders or where you need to get a new bottle.
For just a small amount of money you can get a cup holder extender.
These cup holder extenders have a small base, which is small enough to fit in an regular sized cup holder.
It then has a tapered larger top section to hold bottles up to 3.9 inches in diameter. These are large enough to hold the 32 oz and 40 oz bottles which are only 3.58 inches in diameter.
However, they are not wide enough to hold the 64 oz or 128 oz Hydro Flasks. These sizes are just too big to fit in any cup holder.
Smart Kup (Recommended For 12-25 oz Hydro Flasks)
The Smart Kup is cheap and simple and does the job.
It has a base of 2.6 inches which should fit into any standard cup holder (remember Hydro Flasks start at 2.87 inches) and then expands to 3.2 inches to fit any Hydro Flask from 12 oz up to 25 oz.
There is another top section that can screw onto the bottom section which is even larger and can hold bottles up to 3.9 inches in diameter. So this would work for the 32 oz and 40 oz Hydro Flask bottles.
I recommend this for the smaller sized Hydro Flasks as you can unscrew the top section and just have a smaller adapter which is all you need for the smaller sized bottles.
PFCC Cup Holder Extender with Expandable Base (Recommended For Large Hydro Flasks)
I recommend this for the large sized Hydro Flasks as the base can be expanded by twisting the top of the adapter to expand the base.
Put it into your cup holder and then expand it until you've got a really firm grip. This ensures that it won't fall out or topple over when you're driving