Every football fan has an opinion on the greatest club of all time. Fewer stop to ask a harder question: what does greatness actually mean — and how do you compare it across 138 years of radically different football?
The Club Power Index (CPI) was built to confront that problem directly. Rather than ranking clubs based on popularity, finances, or short-term success, CPI measures historical power — the ability of a club to achieve, sustain, and renew dominance across changing eras of the game.
The Core Challenge: Comparing the Incomparable
Football in 1889 and football in 2025 are not the same sport. Leagues differed in depth, geography, professionalism, and competition density. Some competitions did not exist. Others existed briefly, evolved, or disappeared.
Any honest model must therefore answer three questions:
- How strong was the competitive environment at the time?
- What level of achievement did a club reach within that environment?
- How consistently was that achievement sustained over history?
CPI is designed around these questions.
Era-Adjusted Competitive Context
Not all leagues, regions, or decades are equally competitive. A domestic title won in one era may represent a far steeper challenge than the same title in another.
CPI accounts for this by applying era- and geography-based weighting, reflecting:
- The relative strength of leagues during specific periods.
- The depth and competitiveness of national and continental competitions.
- The historical evolution of football professionalism.
This ensures early dominance is respected without being inflated, and modern success is contextualized rather than assumed superior.
Different Competitions Represent Different Levels of Difficulty
Winning the Champions League is not equivalent to winning a domestic league. Likewise, not all domestic leagues are equally difficult. CPI assigns relative importance to competitions based on the competitive depth. Thus winning a one club dominated league is not the same as winning a highly contested league.
Achievement-Based Scoring (Not Participation)
CPI does not reward participation. It rewards finishing at the top. Only meaningful competitive outcomes are counted, with suitable weight assigned to:
- Major continental competitions
- League titles
- Top-four finishes that reflect genuine contention
Lower placements and domestic cup competitions are deliberately excluded to avoid noise and index inflation.
Competition Hierarchy Matters.
This prevents domestic cup competitions from mechanically padding stats; thereby preserving the reliability of the index. Thus, normalization across time and against peers.
Some Competitions Have Existed Longer
To avoid recency bias, CPI includes outcomes achieved since 1888-89. Thus ensuring that both longevity and the ability of a club to consistently assert itself is rewarded. Thus making it a concurrent living index for football clubs.
Perhaps the most important principle behind CPI is this:
"True greatness is not a single peak, but repeated relevance."
Clubs that rise, fall, adapt, and rise again demonstrate a deeper form of power than those defined by brief golden ages. CPI therefore rewards sustained historical presence — dominance that endures rule changes, wars, tactical revolutions, and economic shifts.
What CPI Is — and Is Not
CPI is:
- A concurrent index
- Era-aware, History aware
- Data-driven
- Quality-conscious
CPI is not:
- A popularity poll
- A financial ranking
- A prediction model
- A fan-bias exercise
It aims to raise the quality of football comparisons and the debates that arise out of them.
Why the Model Is Partially Opaque
The full computational structure behind CPI is intentionally not disclosed in its entirety. This is to protect:
- The integrity of the index
- The calibration behind it
- The risk of oversimplified replication without context
What Matters Is A Living Index
Football history is not static. Nor is CPI. As seasons conclude and context evolves, the index updates — not to chase narratives, but to reflect reality.
The goal is simple: To measure how football power is built, lost, and preserved over time.
Everything else is commentary.