RIP Metric Calculator
Determine the RIP hop-count metric for a path and whether it falls within RIP's reachable range.
Inputs
RIP Metric (Hop Count)
4
Status
Reachable
Hops Remaining Before Unreachable
11
Reachable via RIP?
Yes
Step by step
Values used
Number of Hops = 4
RIP metric
metric = hop_count (0-15 reachable, 16 = unreachable)
RIP Metric (Hop Count)
= 4
Status
= Reachable
Hops Remaining Before Unreachable
= 11
Reachable via RIP?
= Yes
How it works
RIP (Routing Information Protocol) is a distance-vector protocol that uses a simple hop count as its only metric — every router along a path adds 1 to the metric regardless of the link's actual bandwidth or delay, so a path through three routers has a metric of 3. RIP defines 15 hops as the maximum usable distance and reserves the value 16 to mean 'infinity,' i.e. unreachable; this deliberately small diameter limits RIP to small networks, since any destination more than 15 routers away cannot be represented.
Formula
RIP metric
metric = hop_count (0-15 reachable, 16 = unreachable)
- h
- Number of router hops along the path
Frequently Asked Questions
Why does RIP cap out at 15 hops?
RIP's metric field was designed to be small and simple, using a value of 16 to represent infinity/unreachable in a distance-vector protocol that needed a finite way to signal a destination is unreachable. This design choice deliberately limits RIP's usable network diameter to 15 hops, making it suitable only for small networks — larger networks need OSPF, EIGRP, or BGP.
Does RIP consider link speed or delay when computing its metric?
No — RIP (versions 1 and 2) only counts hops, treating a slow 10 Mbps link and a fast 100 Gbps link identically as long as both add 1 to the path metric. This is a key limitation compared to link-state protocols like OSPF, which factor in bandwidth via interface cost.
What happens when a route's hop count reaches 16?
A metric of 16 signals the destination is unreachable via that path (RIP's version of 'infinity'), which routers use to detect and remove failed or looped routes — RIP relies on this along with techniques like split horizon and route poisoning to converge after a topology change, though convergence is notably slower than link-state protocols.