Fantrax is the gold standard for serious fantasy leagues. If you're running a keeper or dynasty league on Fantrax, you already know it offers more customization than any other platform. But with that power comes complexity — especially when it comes to tracking keeper eligibility across a deep roster.
Why Fantrax Is the Best Platform for Keeper Leagues
It's not even close. Fantrax gives commissioners control over virtually every aspect of keeper rules:
- Keeper cost formulas: Salary-based, round-based, flat cost, escalating cost — whatever your league uses, Fantrax probably supports it.
- Keeper limits: Per-team limits, positional limits, tenure-based limits.
- Contract lengths: Multi-year contracts with salary escalators? Fantrax handles it.
- Minor league rosters: Full minor league systems with prospect stashes and call-up rules.
This flexibility is why Fantrax dominates in dynasty baseball, serious keeper football, and deep-roster hockey leagues.
Setting Up Keeper Rules on Fantrax
If you're a commissioner setting up a keeper league on Fantrax for the first time, here's the essential checklist:
1. Choose Your Keeper Type
Fantrax supports several keeper formats under Commissioner → League Setup → Keeper/Dynasty Settings:
- Standard Keeper: Teams keep a set number of players. Simple and clean.
- Salary Cap Keeper: Each keeper has a cost that counts against a cap. Adds a financial strategy layer.
- Dynasty: Keep your entire roster year-over-year with a rookie draft to add new talent.
2. Define Eligibility Rules
This is where Fantrax shines — and where leagues often get confused. Under Keeper Settings, you can control:
- Maximum years a player can be kept
- Whether free agent pickups are keeper-eligible
- Cost increases per year kept (e.g., +$5 per season)
- Whether traded players retain their original keeper cost
Pro tip: Write your custom rules in the league constitution, not just in the platform settings. Fantrax settings cover the mechanics, but edge cases always come up that need human interpretation.
3. Set the Keeper Deadline
Under Commissioner → Keeper Deadline, set a firm date at least 2 weeks before your draft. This gives everyone time to analyze, negotiate trades, and make final decisions.
How to Check Keeper Eligibility on Fantrax
Fantrax has a built-in keeper management screen (Commissioner → Import Players, with the "K" tag). But for managers trying to evaluate their options, the platform's interface can be overwhelming — especially in leagues with complex cost structures.
The main limitations:
- No comparative analysis: Fantrax shows you who's eligible, but not who's a good keeper relative to their cost.
- No league-wide picture: You can see your roster, but not what other teams are likely keeping.
- Manual cost tracking: In leagues with custom cost formulas, commissioners often maintain separate spreadsheets anyway.
Automating Fantrax Keeper Analysis
KeeperTracker integrates directly with Fantrax's API — no CSV uploads needed. Enter your Fantrax league ID and get a full keeper eligibility breakdown for every team in your league.
How to find your Fantrax league ID:
- Go to your league page on Fantrax
- Look at the URL — it'll be something like
fantrax.com/fantasy/league/abc123def456/home - The string after
/league/(before the next/) is your league ID
Note: Fantrax leagues must be public for API access. Most dynasty and keeper leagues on Fantrax are public by default, but check your league settings under Commissioner → League Setup → Privacy if you're getting an error.
The analysis pulls rosters, draft history, and transaction data to determine keeper eligibility for every player on every team. It works with Fantrax leagues in MLB, NHL, and other sports.
Fantrax vs Other Platforms for Keepers
How does Fantrax stack up against the competition for keeper leagues?
- Fantrax vs ESPN: Fantrax wins on customization, minor leagues, and contract support. ESPN wins on ease of use and name recognition.
- Fantrax vs Sleeper: Sleeper has a better mobile app and is free, but Fantrax has deeper league settings and supports more sports for keepers.
- Fantrax vs Yahoo: Yahoo is easier for casual leagues. Fantrax is the choice for anything with complex rules.
For a detailed comparison, check out our platform comparison guide.
Get Started
Whether you're a commissioner setting up your first Fantrax keeper league or a manager trying to figure out your best keepers, the tools exist to make it painless. Preview KeeperTracker — enter your Fantrax league ID for a two-team preview. Full analysis requires a paid pass from $4.99.