Data Sources and Methodology

Play For Keeps rankings and calculations

Dynasty rankings, position ranks, tiers, values, labels and PFK calculations are created by Play For Keeps unless a page identifies a different source. Calculated values are estimates for fantasy football analysis, not official NFL statistics.

Advanced player statistics

Advanced player statistics and snap-count data are sourced from nflverse-data by nflverse, licensed under CC BY 4.0. Play For Keeps selects, combines, calculates, rounds and formats the source fields. The primary inputs are nflverse regular-season player statistics and snap-count datasets.

nflverse data is provided as-is and without warranties. nflverse does not endorse Play For Keeps. Historical values may change when the source corrects data or updates a model.

Player identity matching

PFK joins public football records to Sleeper player IDs with the DynastyProcess player ID crosswalk, published under GPL 3.0. The crosswalk is used during collection and is not offered as a downloadable PFK dataset.

Sleeper information

Player identity, team, position, league and game information may come from Sleeper. Sleeper and its data owners retain their rights. Play For Keeps is independent and is not sponsored or endorsed by Sleeper.

Metrics PFK does not recreate

The free PFK suite does not relabel or estimate proprietary charting metrics such as routes run, yards per route run, first-read target share, yards after contact, missed tackles forced, contested-catch rate, drop rate, PFF grades, big-time throws or turnover-worthy plays. Those require complete charting data or separate written permission.

Downloads and shared images

Any PFK image or data export containing CC-licensed advanced statistics keeps a compact source and license credit because the export can travel separately from this webpage.