Draft Visualizer

Take control of your Underdog Fantasy draft portfolio with the rosterOS Draft Visualizer, a powerful, private, and intuitive analytics tool. Instantly upload your Underdog CSV and unlock in depth insights on your player exposures, roster construction, unique stacking trends, and more, all presented with interactive charts and tables.

No logins, no data sent to servers. Your information is analyzed securely and instantly right in your browser.

Whether you’re optimizing for winning lineups or chasing screenshot equity with bold, brag-worthy builds, level up your draft strategy and gain the edge you need to dominate your leagues this season!

How to Use the rosterOS Draft Visualizer

  • Export Your Draft Data from Underdog

    • Log in to your Underdog Fantasy account.

    • Go to your completed NFL 2025 Season drafts.

    • Find the “Email exposure CSV” option and export your draft results as a CSV file.

    • Save the file to your computer.

  • Upload Your CSV File

    • Open the rosterOS Draft Visualizer website in your browser.

    • Click the “Upload CSV” button at the top.

    • Select and upload your Underdog CSV file.

  • Explore Your Draft Portfolio

    • Once uploaded, your data is processed right in your browser (your data never leaves your device).

    • Use the navigation to explore:

      • My Players: See all the players you’ve drafted, including exposure, average draft position (ADP), and closing line value (CLV). Filter by name, team, position, or ADP range.

      • My Teams: Browse all your teams. Filter for specific player combinations, view team CLV, and see positional/game stack breakdowns.

      • Combos & Recommendations: Discover your most common 2-player combos and see recommended player pairs you haven’t drafted together.

      • Charts: Visualize your draft habits with interactive charts, including positional percentage by round, unique players by team, positional breakdowns, draft slot distribution, and team structure histograms.

  • Tips & Privacy

    • All data stays on your device; nothing is uploaded or shared.

    • Use filters and sorting to analyze your portfolio in detail.

    • For the most up-to-date analysis, export your latest Underdog drafts and re-upload them here.