rosterOS Best Ball Overlay

Best Ball draft overlay for Underdog with player grades, roster guidance, stack analysis, and exposure tracking.

RosterOS is a free, private draft overlay built for Underdog best ball drafters. It sits inside your draft room and combines live board context with ADP and rank data so you can make faster, smarter picks on the clock. See value vs reach, roster fit, position scarcity, stack opportunities, and portfolio exposure all in one place without switching tabs or doing mental math. WHAT IS IN THE OVERLAY PLAYER BOARD Live board with search, position filters, and sort by Rank, Grade, or ADP. Grade-driven layout for fast scan-and-decide workflows. Expanded rows for deeper pick context when you want it. PLAYER BADGES STK (QB Stack): Appears when a pick creates a same-team QB stack. Shows on a QB if you already have that team's skill player, or on a skill player if you already have that team's QB. LEV (Leverage): RB-only. Highlights the best-ADP handcuff behind a top-20 RB already drafted by another team in the room. QB (Back-Stack Available): WR/TE/RB-only. From Round 8 on, when you have one QB or fewer, flags skill players whose team still has a ranked QB available later, keeping a correlation path open. GRADE PILLS Value or Reach: How the pick price compares to ADP context. Build Fit or Build Miss: Whether the pick supports the shape your roster is taking. Scarce or Can Wait: Whether this position or profile might be gone before your next turn. Stack pills: Same-team correlation opportunities tied to your current roster. Neg. Correlation: Flags picks that work against what you have already built. STACKS TAB Your active stacks grouped by team. Available QB Stack Targets that pair with your roster. Back-Stack Candidates showing QBs whose skill players you already own. ROSTER TAB Emerging Build: The draft pattern your roster is starting to form. Capital by Position: Where your picks are going positionally. Roster View: ADP value and rank value per pick, by position. Combo Ownership: How your player pairings compare to the field so you can spot chalk and find differentiation. DRAFT PREFERENCES Strategy Preference: Set positional tendencies by position group. Rank Trust: How much weight grades put on your rankings vs ADP. Very Low to Very High. Stack Aggressiveness: How hard the overlay pushes stack and correlation opportunities. Very Low to Very High. Playoff Stacking: Tune how heavily the overlay weights playoff-week correlation paths. Week 17 Boost: Tune how much favorable Week 17 situations factor into grades. Capital Penalty: How much roster concentration is penalized in the grading. HOW IT WORKS Opens automatically when you join an Underdog draft. Reads live board context and applies your preferences in real time. Updates grades, badges, stack signals, and roster feedback as picks happen. GETTING STARTED Install RosterOS and pin it to your Chrome toolbar. Open the popup and run through the quick onboarding to connect your Underdog account and pull in your draft history. Join any Underdog draft and the overlay appears automatically. Use the Player Board, Stacks, Roster, and Draft Preferences tabs during your pick windows. If the overlay does not show up, refresh the draft tab and confirm Overlay Enabled is on in the popup. SYNCING YOUR UNDERDOG PORTFOLIO Open the popup and go to the Underdog Sync tab. Visit any Underdog page while signed in and RosterOS picks up your session automatically. No password needed. Hit Sync from Underdog to pull your full draft history in one click. Filter by tournament type if you want to focus on a specific part of your portfolio. Re-sync anytime after you finish new drafts. UPLOADING A CSV INSTEAD Export your draft history from Underdog and upload it under Exposure CSV in the popup. Apply tournament filters to focus your exposure view. Swap or remove it anytime. CUSTOM RANKINGS Upload a rankings CSV with Name and Rank columns. Rankings apply immediately and can be replaced anytime. WHY BEST BALL DRAFTERS USE IT The pick clock is short. RosterOS puts everything you need in front of you so you are not guessing. Value and reach calls get easier when the context is right there on the board. Stack and back-stack paths are flagged automatically so you never miss a correlation window. Your portfolio exposure is built in, so you can see when you are doubling up on pairs you already own. Playoff Stacking and Week 17 Boost mean late-season upside is baked into your build decisions from round one. FREE AND PRIVATE Free to use with no account required. Your Underdog session and draft data never leave your browser. Everything is processed locally on your device. Preferences and uploads are stored in extension storage, not on any server. IMPORTANT NOTE RosterOS is built for Underdog drafts only. It is not affiliated with, endorsed by, or sponsored by Underdog.