Rating Methodology

FragLedger separates source data from derived metrics. This page defines the current preview method, the sample each number uses, and where the calculation can mislead.

01 · Provenance

Three labels, three meanings

Valve data

CS Rating, match identity, and available account fields supplied by Valve or Steam.

Shown as · Valve

Demo parsed

Rounds, kills, damage, assists, trades, utility, and other events reconstructed from the match demo.

Shown as · Demo parsed

FragLedger calculated

Aggregates and ratings computed from an explicitly named match sample using the formulas below.

Shown as · Method v0.2

02 · Definitions

Component metrics

K/D: Total kills ÷ total deaths in the selected match sample. A death count of zero is reported separately rather than forcing a denominator.
ADR: Total player damage ÷ rounds in the selected sample. Production aggregates are round-weighted, not a simple average of match averages.
HS%: Headshot kills ÷ total kills. This describes kill finish location; it is not an aim-quality score by itself.
KAST: Percentage of rounds with at least one kill, assist, survival, or trade. One qualifying event is enough for the round.
CS Rating: Valve's Premier rating. FragLedger stores and displays it but does not redefine or blend it into Frag Rating.

03 · Derived rating

Frag Rating v0.2

The preview rating is a compact performance index centered near 1.00. It combines survival-adjusted fragging, damage, and round participation. It is deliberately not presented as a complete measure of player skill.

Per-match formula

1.00 + 0.28 × (K/D − 1.00) + 0.32 × ((ADR − 75) / 75) + 0.24 × ((KAST − 70) / 70)

Output bounded from 0.35 to 1.85 · Unavailable when deaths or rounds are zero · Preview calibration only

K/D component

0.28

Rewards fragging efficiency while limiting its influence.

ADR component

0.32

Captures damage contribution beyond final blows.

KAST component

0.24

Credits survival, assists, and traded round impact.

04 · Account context

Lobby signals

Lobby Scan presents available account facts such as verified ban history, account age, CS2 hours, and unusual rating-to-hours combinations. The current preview groups those signals by attention level; it does not predict cheating or label a player's current behavior.

Unknown data must remain unknown. A missing ban record, private playtime, or unresolved Steam identity is never silently converted into a clean result.

05 · Known limitations

What v0.2 does not know

Role and position context are not yet modeled. A dedicated anchor and an entry player should not be judged identically.
Opponent strength, economy difficulty, clutch leverage, and round-win probability are not yet part of the headline rating.
Small samples are volatile. FragLedger shows the number of matches and rounds so the viewer can judge confidence.
Zero denominators remain unavailable: K/D and Frag Rating require at least one death, ADR and KAST require at least one round, and HS% requires at least one kill.
The current public build uses deterministic fictional fixtures. It demonstrates the method but does not make claims about real players.
Preview round timelines deterministically reconstruct fictional kill and bomb events from the fictional scoreboard for interface testing. They do not claim real timing or weapon telemetry, and grenade evidence remains unavailable instead of being guessed.

Change log

Method history

v0.2

Published the explicit preview formula, bounded output, source labels, limitations, and unknown-data policy.