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This web page lists switches that do not have spare ports for one or more VLANs.

What is a spare port?
A spare port is an inactive port that is configured for a VLAN other than VLAN 1 (remember, VLAN 1 is for unused ports). Spare ports are intentionally configured on real VLANs even though there may be nothing actually connected to the port. Spare ports have switch port labels that say "SPARE".

Why have spare ports?
We use spare ports for two reasons:

1. To speed up activations
   When a new connection needs to be made to a VLAN, we have to identify the nearest switch to the site where the connection is needed, find an unused port on the switch, configure the port onto the VLAN, and connect a patch cable. Only then can the new connection be tested. This process goes faster if there's already a spare port for the VLAN on the switch.
2. To provide on-site laptop access for network engineers
   When a network engineer is on-site, physically near a deployed switch, s/he may need access to the switch's command-line interface. The serial console port can be used to execute "show" commands and other configuration commands, but doesn't provide access to the Internet for email or to tftp new software into the switch. By permanently allocating a known port on each switch as a spare, physical access to switches is enhanced.

This web page lists, for each switch, the number of ports configured in each VLAN and and the number of such ports that are inactive. To use it, find the switch you want, scan across to the column for the VLAN you want, and see the total ports configured in the VLAN and the number of those ports that are inactive (spare). To find the actual spare port(s), click on the switch name and manually search by VLAN number.