Go Back   AnandTech Forums > Hardware and Technology > Cases & Cooling

· Hardware and Technology
· CPUs and Overclocking
· Motherboards
· Video Cards and Graphics
· AMD Video Cards
· Nvidia
· Displays
· Memory and Storage
· Power Supplies
· Cases & Cooling
· SFF, Notebooks, Pre-Built/Barebones PCs
· Networking
· Peripherals
· General Hardware
· Highly Technical
· Computer Help
· Home Theater PCs
· Consumer Electronics
· Digital and Video Cameras
· Mobile Devices & Gadgets
· Audio/Video & Home Theater
· Software
· Software for Windows
· All Things Apple
· *nix Software
· Operating Systems
· Programming
· PC Gaming
· Console Gaming
· Distributed Computing
· Security
· Social
· Off Topic
· Politics and News
· Discussion Club
· Love and Relationships
· The Garage
· Health and Fitness
· Home and Garden
· Merchandise and Shopping
· For Sale/Trade
· Hot Deals with Free Stuff/Contests
· Black Friday 2014
· Forum Issues
· Technical Forum Issues
· Personal Forum Issues
· Suggestion Box
· Moderator Resources
· Moderator Discussions

Thread Tools
Old 10-19-2009, 05:56 PM   #1
Join Date: Jan 2005
Posts: 50
Default How do I measure case fan size?

I'm noob here,

Can someone give me a straightforward answer on how to measure a fan size? I've found the following answers in various web places, which are all different on my fan:

1) measure the distance between the mounting holes
2) measure the outside of the case
3) measure the blades from tip-to-tip.

Perhaps someone could take a fan that they know is an 80mm fan, for example, and measure to find out what exactly it is that's 80mm?

tbob is offline   Reply With Quote
Old 10-19-2009, 07:23 PM   #2
MustISO's Avatar
Join Date: Oct 1999
Location: USA
Posts: 11,356
Default How do I measure case fan size?

It should be edge to edge.
HEAT 107-0-0
MustISO is offline   Reply With Quote
Old 10-19-2009, 10:06 PM   #3
Elite Member
Join Date: May 2001
Location: Finger Lakes area NY
Posts: 18,998
Default How do I measure case fan size?

Generally the metric measure is across the flats, but that is just a convenient approximation as the mm are almost never truly at the 10s (i.e. the 120 is actually 119, etc.). The measure that needs to be accurate is the dimension between the mounting holes (on center) on the diameter. 80mm is 4" on centers, 120mm is 5-7/8" on centers, etc. The standards were pretty much set by the US companies which made the first muffin fans before metric took over the world...

Here's an example:

Zepper is offline   Reply With Quote
Old 10-20-2009, 10:34 AM   #4
Platinum Member
Borealis7's Avatar
Join Date: Oct 2006
Posts: 2,249
Default How do I measure case fan size?

or...you can measure the diagonal and divide by the square root of 2
Jesus Saves. The rest of you take 2d10 Fire Damage.

i5 2500K @ 4.4GHz / Noctua NH-C14 | GA-Z77X-D3H | ZOTAC GTX680 | 8GB DDR3-1600 G.Skill | Samsung S23A700D 120Hz | SeaSonic 650W PSU
Borealis7 is offline   Reply With Quote

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 08:24 PM.

Powered by vBulletin® Version 3.8.8 Alpha 1
Copyright ©2000 - 2015, vBulletin Solutions, Inc.