VMware VMFS Datastore Sizing Calculator

How to Use the calculator:

Input Fields :

Total Number of VMs : Enter total number of VMs in the Infrastructure
Number of VMs in Single VMFS Datastore : Min Value : 1 : Max Value : Follow the best practices usually 10-15 VMs
Total Disk Size for the VM (GB) : Enter combined disk size for all the disks the VM will have
Memory Assigned per VM (GB) : Enter the memory value , Max 1 TB
Total IOPS per VM : Enter your IOPS value for a given VM , for server virtualizations it’s usually 30-40 IOPS per VM
Read Ratio % :Enter your expected read ratio ,combined value with write should not be more than 100
Write Ratio % :Enter your expected write ratio,combined value with read should not be more than 100
RAID Level : Enter your appropriate RAID level , this will be used for calculating Write Penalty
Disk RPM : Enter the RPM value of the Disk

Output Value :

Total Size of a Single VMFS Datastore(GB) : Tells you the size of a Single VMFS volume , calculation takes into account snapshot and free space recommendations
Total No. VMFS datastores : Tells you how Many datastores you need with above mentioned capacity
Spindles Required for a Single Lun : Tells you how many disk spindles you require for a given Lun, value doesn’t take into account decimal calculations
Spindles Required for all the Luns : Tells you total spindles which is required in your environment for all the Luns

9 thoughts on “VMware VMFS Datastore Sizing Calculator

  1. Hi Samir,
    here Auguste from Cameroun
    This blog is very helpfull for me .
    I am just starting with VMware Technologie which i find very interesting. Currently I own the 3 new VCAs. I am also preparing for the VCP5 exam .
    Want to know if I can ask some questions here in your blog

  2. Hi Samir,

    Great tool. I plan to use it for my work. Is there an Excel of the same, which is shareable ?

    The idea is to put this as a tab in Excel while I build my overall costing for a given customer proposal.


    • It’s based on an excel calculation, however I am not sure how this is going to help you in a costing proposal. That should be part of the overall storage sizing and not just VMFS.

  3. Pingback: Dimensionnement d’une Banque de données | Damien Riviere

Leave a Reply

Your email address will not be published. Required fields are marked *


two × 6 =