Routing Health Score Calculator
Score routing health from convergence, table utilisation, flap rate, session state and path redundancy.
About Routing Health Score Calculator
Each dimension is scaled so that a healthy network scores near 100, then combined with weights that reflect what actually causes outages — convergence and stability carry the most, table headroom the least because it degrades gradually rather than suddenly. A single trend line is what gets routing health onto a management dashboard, and surfacing the weakest dimension keeps the score actionable instead of decorative.
Formulas
Routing Health Score
Score = 25% convergence + 20% stability + 20% session health + 20% path redundancy + 15% table headroom, each dimension normalised to 0–100.
- convergence
- 100 minus the percentage by which measured convergence overshoots the target
- stability
- 100 minus 5 points per route flap per hour
- session health
- 100 minus 4 points per percent of routing sessions down
Capacity scoring
Table headroom score = 100 − 2.5 × (utilisation − 60), so it only penalises above 60%.
Worked example
With the default values below, Routing Health Score Calculator returns Routing Health Score of 81.3. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Measured convergence timeminimum 0 ms
- 1,200 ms
- Convergence targetminimum 1 ms
- 1,000 ms
- Route table utilisationaccepts 0–100 %
- 62 %
- Route flaps per houraccepts 0–1,000 flaps
- 8 flaps
- Routing sessions downminimum 0 sessions
- 1 sessions
- Total routing sessionsminimum 1 sessions
- 40 sessions
- Prefixes with a backup pathaccepts 0–100 %
- 85 %
Results
- Routing Health Score
- 81.3 /100
- Rating
- B — Good
- Convergence Score
- 80.0
- Route Stability Score
- 60.0
- Session Health Score
- 90.0
- Weakest Dimension
- Route stability (flapping) at 60/100
Step by step
- 1Values used
- 2Routing Health Score
- 3Capacity scoring
- 4Routing Health Score= 81.3 /100
- 5Rating= B — Good
- 6Convergence Score= 80.0
- 7Route Stability Score= 60.0
- 8Session Health Score= 90.0
- 9Weakest Dimension= Route stability (flapping) at 60/100
Assumptions and limits
- The result is derived only from the 7 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Routing Health Score calculated?
Score = 25% convergence + 20% stability + 20% session health + 20% path redundancy + 15% table headroom, each dimension normalised to 0–100. Each dimension is scaled so that a healthy network scores near 100, then combined with weights that reflect what actually causes outages — convergence and stability carry the most, table headroom the least because it degrades gradually rather than suddenly.
Why does Routing Health Score matter?
A single trend line is what gets routing health onto a management dashboard, and surfacing the weakest dimension keeps the score actionable instead of decorative.
What values do I need to enter?
This calculator takes 7 inputs: Measured convergence time, Convergence target, Route table utilisation, Route flaps per hour, Routing sessions down, Total routing sessions, Prefixes with a backup path. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.
Is the weighting authoritative?
No — it is a defensible default, not a standard. Reweight it for your environment: raise path redundancy if you carry real-time media, raise table headroom if you are close to a FIB limit, and keep the weights fixed afterwards so the trend stays comparable.