ip prefix-list · ge / le

Prefix-List Range Calculator

Enter a prefix and an optional GE or LE range. The calculator shows which prefix lengths match and lists every subnet the entry will permit or deny.

Prefix

Range

Exact GE LE GE + LE

Try

List name

Prefix lengths

Shorter than the prefix (never matches) Lengths that match Longer than the range

Bit map of the network

Fixed: must equal the prefix Can vary within matched subnets Host bits, beyond the longest match

Subnets that match, by length

Test a route

Route to check

prefix/len alone matches only that exact prefix and length.

ge N matches lengths N up to /32 (or /128 for IPv6). le N matches lengths from the prefix length up to N. Both together match N_ge through N_le.

IOS requires len < ge ≤ le ≤ 32, and len < le when only LE is used. A route matches when its first len bits equal the prefix and its length falls inside the range.