Skip to content
Calcrivo

VPN Health Score Calculator

Grade a VPN tunnel out of 100 using uptime, rekey failures, latency, loss and delivered throughput.

Inputs

%
events
ms
%
%

VPN Health Score

81.2/100

Grade

B — Good

Uptime Sub-score

88.0/100

Rekey Stability Sub-score

76.0/100

Suggested Action

No action needed

Step by step

  1. Values used

    Tunnel uptime over the period = 99.40 %; Failed rekeys in the period = 2 events; Tunnel round-trip latency = 60 ms; Packet loss inside the tunnel = 0.3000 %; Delivered share of expected throughput = 88 %

  2. VPN Health Score

    score = 0.3 × uptime + 0.2 × rekey stability + 0.2 × latency + 0.15 × loss + 0.15 × throughput sub-scores.

  3. VPN Health Score

    = 81.2 /100

  4. Grade

    = B — Good

  5. Uptime Sub-score

    = 88.0 /100

  6. Rekey Stability Sub-score

    = 76.0 /100

  7. Suggested Action

    = No action needed

How it works

Uptime dominates because a tunnel that flaps is worse than a slow one, and repeated rekey failures are the classic symptom of mismatched lifetimes or proposals between peers. The remaining weight is split across the performance metrics users actually feel. Tunnel dashboards show up or down; this turns the softer signals — rekey churn, MTU-driven loss, throughput shortfall — into a trend you can act on before the tunnel drops.

Formula

VPN Health Score

score = 0.3 × uptime + 0.2 × rekey stability + 0.2 × latency + 0.15 × loss + 0.15 × throughput sub-scores.

uptime sub-score
Linear from 0 at 95% availability to 100 at 100%
rekey stability
100 minus 12 points per failed IKE or child SA rekey

Frequently Asked Questions

How is VPN Health Score calculated?

score = 0.3 × uptime + 0.2 × rekey stability + 0.2 × latency + 0.15 × loss + 0.15 × throughput sub-scores. Uptime dominates because a tunnel that flaps is worse than a slow one, and repeated rekey failures are the classic symptom of mismatched lifetimes or proposals between peers. The remaining weight is split across the performance metrics users actually feel.

Why does VPN Health Score matter?

Tunnel dashboards show up or down; this turns the softer signals — rekey churn, MTU-driven loss, throughput shortfall — into a trend you can act on before the tunnel drops.

What values do I need to enter?

This calculator takes 5 inputs: Tunnel uptime over the period, Failed rekeys in the period, Tunnel round-trip latency, Packet loss inside the tunnel, Delivered share of expected throughput. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.

You might also need