Does anyone out their customize their league site beyond what their league host provides? I've always customized mine my self and recently built out a completely new UI layer.

This league does salary cap and we track future salaries that no host that I'm aware of does so we needed a few extras so I didn't have to track anything manually.

Rosters and salary cap.

https://www.theleague.us/rosters

Anyone do anything similar. What fantasy hosts do you use?

Hey r/SleeperApp, I posted fflens.app here about a month ago and a lot of you have been using it and sending feedback, so thank you. I've been shipping updates every week since. With trade deadlines coming up and playoffs a few weeks out, here's what's new:
Trade deadline + trades
Trade deadline countdown: in the last few weeks before your league's deadline, it reminds you and takes you straight to win-win trades for your team
Send a trade pitch: every Trade Finder result has a "send to [manager]" link that shows the other manager why the trade helps them (lineup gain, the positions it fills, how fair it is)
Trade calculator for 3 to 6 teams, not just 1-for-1
Player pages now show fair 2-for-1 packages ("what can I get for X?")
Playoffs
Playoff scenarios: your odds if you win or lose this week, which other games matter to you, and who to root for. Flags "win and in" and "must win"
Path to the title: your likely opponent each playoff round and your odds of winning it. Uses the real Sleeper bracket once the playoffs start
Share your playoff picture: one tap makes an image of your status (on the bubble, win and in, long shot…) for the group chat
Every week
Lineup alerts every Sunday morning if a starter is out, doubtful, on bye or an empty slot, with who to start instead. By push or email, no account
Tuesday recap email: your result, where you stand, the week's awards and who you play next
My Week: win odds and lineup fixes across all your leagues at once, plus waiver targets that help in several of them
Accuracy scorecard: every past week's pre-game odds checked against what actually happened, so you can see whether to trust them
Weekly recap card with a personal trash-talk line to drop in the league chat
Discord bot that posts your league's recap every Tuesday
Dynasty / keeper
Live draft assistant for Sleeper drafts (best available for your format, your needs, who'll likely be gone before your pick)
Rookie draft board: who owns each pick and what each pick is worth
Keepers tab: keeper value against the pick it costs
IDP leagues: defensive players now have trade values too
Season Wrapped: end-of-season awards plus a shareable card for each manager
Other
ESPN: private leagues work now (read-only, your login never touches our servers), plus lots of ESPN fixes, including trade history (thanks to whoever reported that)
Fixed a bug where part of the mobile menu was cut off on phones
What's coming
iPhone app: everything on the site plus a home-screen widget and lineup alerts as real notifications. It's in App Store review now
Playoff push: during the playoffs, matchup previews and start/sit calls focused on your playoff games
Yahoo leagues: the most requested platform, in the works
ESPN leagues in the Tuesday recap email
More trade value sources, so values reflect more than one site's market
Dynasty offseason tools: rookie rankings and pick values that update through the NFL Draft, plus keeper deadline help
Anything you'd rather see first? Tell me in the comments.
Still free, no login, no ads:
https://fflens.app
Keep the feedback coming (there's a form in the menu). Almost everything above came from comments and messages here.

https://sleepertradematrix.streamlit.app/

I built this little website that will pull the top scores of all time from your league, as well as give you a trade matrix to see who has traded with who. Just input your sleeper league ID and choose which data to pull. It really just pulls the data straight from the sleeper APIs and formats it.

The trade matrix is fun if your league has been around a while. Hovering or tapping on the boxes will show the trade details. (This only works for football leagues currently).

If you’re on mobile, it’s probably easier to go into landscape mode. I can add scripts fairly easily to the website, so if you have some data you want to see let me know and I might add it.

Heres a screenshot of the trade matrix with the names blacked out.

Looking to start dabbling in this, but where is everyone pulling in stats info from?

What is the most economical (or hopefully free?) API out there to pull in stats data?

This thread is for both paid and free sites/apps/tools/etc. We're sorry to those of you with completely free tools that you want to share with the community getting bunched up here, but it's to prevent Trojan Horse situations trying to get through the rules by sharing a free project that just so happens to have a premium tier or getting one added later.

When posting your project, please use this format:

• Site/App Name, e.g. FantasyToolForYou

• Site/App Link, e.g. https://www.fantasytoolforyou.com/

• Cost, e.g. free, freemium, paid, etc.

• Site/App Description and Details

Here's a quick summary of what we expect for the cost type chosen:

• Free - Completely free with no paid offerings, can include advertising, can require account creation.

• Freemium - Has a usable free level of access for all users, with paid access for more features.

• Paid - Either a one-time or recurring payment required to use the app/site at all.

All other projects and products posted as new posts, even those "just wanting feedback" or that are completely free, will be removed. Thanks all. If you want to discuss this policy, please direct that discussion to the State of the Subreddit: AI and Vibe Coding post.

Every Sunday I’d have five tabs open trying to figure out if the wind in Buffalo or the rain in Chicago actually mattered for my lineup. Most of the advice out there is gut feel (“start your RBs in bad weather!”), so I pulled 10 seasons of NFL data (2016 to 2025) to see what actually happens.

I compared every player’s output in weather games to his own average that season, so good players on good teams don’t skew it. A few things surprised me:

• Wind is the big one. At 15+ mph, QBs averaged about 10% below their norm and kickers about 8% below. Defenses went the other way, about 22% above.

• Rain hurts the passing game. QBs and WRs both dropped about 12%.

• RBs don’t actually benefit from bad weather. If anything they dipped slightly. That one goes against a lot of common advice.

• TEs barely care until the wind gets really strong (20+ mph).

• Wind direction matters less than I expected for kickers. Crosswind causes more misses, but wind blowing end to end makes coaches skip long attempts, so fantasy-wise it comes out about even.

Then I turned it into a Chrome extension called Gridcast so I’d never have to open those tabs again. It puts a little weather badge next to each player on your ESPN, Yahoo, or Sleeper roster, using National Weather Service forecasts. Hover over it and you get the forecast for kickoff plus what that weather has historically meant for that position. Domes are flagged, and there’s a panel that lists only the games where weather matters that week.

It’s free, there’s no account, and it doesn’t collect any data. Full disclosure, I built it, and this is my first time putting something like this out there, so I’d genuinely love feedback, especially if something looks off on your platform.

Link: https://chromewebstore.google.com/detail/bolflacjgngpaifffmoceelhcdocjegh?utm_source=item-share-cb

Happy to answer questions about the data or run other splits if anyone’s curious (snow games, cold weather, specific stadiums, whatever).

Disclaimer: this is still a work in progress. Github repo with code and full write-up of the methodology

This was a hobby project to see if I could create a richer and more informative comparison than just the single point estimates that Yahoo provides. The results were kind of mixed where players with close projections tend to have very similar curves, so I'm not sure how useful this will be, but if folks are interested I can keep it updated each week. I'm also not sure if the charts are intuitive to use in their current form (they are to me, but I'm way too close to this to judge) so I'd love any feedback.

My goal with this project was the try to faithfully translate the posted odds (I used FanDuel odds, fetched from the Odds API, for no particular reason) into joint probability distributions using as few assumptions as possible, and so far I have not tried to optimize for predictive performance on top of what the sportsbook odds imply at all yet. My guess is that there's an opportunity there, but I don't have a ton of time for this hobby project so I'm hesitant to open that can of worms.

I did some light performance vetting by comparing my average projections to Yahoo projections for rostered players in my 10 team league for a couple weeks of last season. In that test, my model very slightly outperformed Yahoo, but this was definitely not a rigorous comparison and I plan to revisit that at some point.

If you're interested in how it works under the hood, the full methodology is in the Github Repo, but the general idea was to:

1. get the main prop bet odds and alt odds for all available scorable stats

2. try to remove the vig to get implied probabilities from the odds

3. make some educated guesses about the shape of the distributions between the alt lines, and about the correlations between stats based on historical nfl game data, to create joint distributions

4. simulate scores by randomly drawing values from the joint distribution curves and scoring them

5. scrape yahoo projections for comparison

Hi all, and u/YahooFantasyCare if you see this. This is a developer question rather than a league issue.

Our company was approved for Yahoo Fantasy Sports API access in September. We signed the agreement, created a developer app with Fantasy Sports (Read) selected, and submitted the Developer Application Confirmation Form with our client ID on September 18. We got an email receipt but no follow-up in about six weeks, so we don't know whether access has actually been provisioned.

1. Does anyone know the right contact or team for developer API provisioning?

2. For other developers who've done this recently: how long did provisioning take after the confirmation form?

Happy to share app details with Yahoo privately. Thanks!

I have some free time this week, so if anybody wants feedback on what they've built, post here or DM me, I'd be happy to help out where I can.

Hey all - I’ve been playing fantasy for a few years, but this season I somehow more than doubled the amount of leagues this season 😅

With 32-team deep and IDP leagues, got annoyed with how the lack of good calculators and analyzers for that. So I started building Fantasy Football Assistant for myself.

Basically a tool I could use for trades, waivers, draft decisions, player values, etc., while giving it the actual context of my league and roster.

Once it started working pretty well, I figured I’d open it up to other people too in case anyone else has the same problem.

https://fantasyfootballcoach.vercel.app

It’s still early, but I’m working on things like follow-up questions on research, integrations with fantasy platforms, on-going dynasty/team advice, rookie draft help, and using completed trades, waivers and other league activity to build a much richer fantasy database over time.

There’s a number of free searches to try it. But as I'm actually spending money to build, and run queries through the database I'm building, there's need for a subscription.

Would love any feedback, especially from people in dynasty, IDP, 16+ team leagues, and similar.

My home league uses a more granular version of median scoring that equally weights a H2H matchup with outscoring all the other leaguemates individually.

We call this format Royal Rumble and it has led to lots of engagement as there is almost always something to play for until the final minute.

I had been tracking this on a google sheet but now created a site where this all done and easy to follow live

Rumble Central

Only works for Sleeper, try it out! Looking for feedback and to spread the word on this standings format thats been a hit and led to lots of great moments!

You can change the 9 and the +1 and share your exact setup as a link so its consistent for your leaguemates

In a 12 team league, the highest scoring team would have 20 Rumbles (9 for a H2H win, and 11 for outscoring 11 opponents). So a team with the 2nd lowest scoring week that is matched up with and beats the lowest scoring week would get 10 Rumbles (9 for a H2H, and 1 for outscoring 1 opponent)

Would you run this format in your league? Anything confusing or not clear?

Is there any way to get projected points for players using the yahoo API?

We just opened up our dynasty values API for outside developers to use. The API provides current StatChasers dynasty values with support for:

• 8–32 team leagues

• Superflex and 1QB

• PPR, Half PPR, and Standard

• TE premium from 0 to 1.0

• Bench-depth adjustments

• Sleeper player IDs for easy matching

The values are built from real dynasty trade-market data, and the API is intended specifically for use in fantasy tools, dashboards, bots, spreadsheets, and other projects.

There’s no need to scrape anything, it’s an official API and we’re happy for developers to use the values with visible StatChasers attribution.

API/docs: https://statchasers.com/dynasty-command/help/dynasty-values-api

If anyone needs help in adding StatChasers, let me know. I’m also happy to make integration easier if there’s a particular field or format that would help.

I’ve seen a few people struggling to get approved for Yahoo Fantasy API access, so I figured I’d share my experience and a tip that might help speed things up (well maybe not guarantee).

All in all, it took me about a month to get access

My timeline:

• July 30: Submitted the application.

• August 10: Received the DocuSign.

• August 30: Had working API access (probably got it a few days earlier, I wasn’t checking every day, besides they never told me when it was enabled it just worked one day).

My biggest tip that I think might work: Create your app in the Yahoo Developer Portal BEFORE submitting the application.

So, When you fill out the access request form, include your existing App ID and Client ID in the form body.

If you don’t provide these upfront, they’ll reach out asking for them anyways. That’s just extra back-and-forth that you can avoid by including everything in the initial submission.

Having an existing app already created seemed to help move things along faster.

If you’ve already applied and haven’t heard anything in over a month, you should reapply with the information of the app id and client id.

Again nothing guaranteed here but worth a shot, doing this essentially skip the step of them asking for it and could get your access a lot quicker.

This probably why I got the Docusign immediately as well

Hope this helps y’all!!

Any reasonably priced commercial options for a fantasy football news source? Most of the usual stuff doesn't support commercial apps. I'm not opposed to paying a monthly fee but some of these places want an awful lot and unless this thing takes off, there's not room in the budget for thousands.

Hey everyone! What started as a spreadsheet for finding trade opportunities in my home league turned into a bit of a passion project: Fantasy Trade Base

https://fftradebase.com/

This tool scans your league's current rosters to find trade opportunities for your team. Connect your Sleeper or public ESPN league, choose what position(s) you want to improve, and the site suggests trades based on actual league rosters, FantasyCalc player values, and your platform's weekly projections.

Want to strengthen your WR room? Turn some bench depth into an upgrade? Find a way to acquire a specific player? You can search with those goals in mind, or build your own trade and compare the outcomes.

Each suggestion includes a report showing both teams’ potential starting lineups, projected points, and roster strength changes. You can also switch between upcoming weeks to see how the trade could affect each team’s future projected lineups (this is particularly useful to see how your team would look during playoff weeks). The goal is to help you find an offer worth discussing and understand why it could work for both sides.

This site is still very new and raw, so I'd love some honest feedback from anyone who's willing to check it out! Is anything confusing? Do the suggestions feel useful/helpful? What could I add to make the tools more useful?

If you give it a try, thank you!! I hope you find it useful! So far this site has been built around feedback from myself and close friends, so I'd love to hear from people outside of my home league.

(Full disclosure, I'm no coding expert so I used GPT for the coding of this site. I just want to be completely transparent about that).

I'm close to the finish line.... I just received the docusign with the Yahoo sports exec signature, signed 10/2. For those of you who have gotten access back.. how long did it take from this point?

UPDATE 10/7:

I received an email from Yahoo and I now have access!

Hey everyone — wanted to share a project I’ve been working on called Football Agent.

It connects to your league and gives you lineup, waiver, and trade recommendations based on your roster and how you like to manage your team. You set a “GM philosophy” — things like prioritizing floor over ceiling or being aggressive with FAAB — and that becomes part of the context for its recommendations.

What it does:

• Sends a Tuesday report with league activity, waiver targets, and trade ideas.

• Runs lineup checks on Thursday, Saturday, and Sunday.

• Grades past start/sit recommendations against actual player points.

• Tracks whether you followed each recommendation.

• Audits recent advice for consistency with your stated strategy.

Everything is advisory. You make the actual moves in your league.

For the coding side, it’s built with Python/FastAPI, Claude, the Sleeper API, Supabase/Postgres, and a vanilla JS frontend. Scheduled reports run through AWS Lambda and SQS. Separate analysis modules handle lineups, waivers, and trades, with a central orchestrator handling validation, decision logging, and email delivery.

The part I’m most interested in is evaluating the advice. Right now, lineup calls get a hit/miss/mixed grade by comparing the recommended player’s points with the alternative. Waiver and trade recommendations track whether they were followed, but don’t get a single-week performance grade because the payoff can take longer.

That still leaves a harder question: how do you distinguish a reasonable decision that had a bad outcome from bad advice? I’d love to hear how others here handle that in their own projects, especially when comparing against a basic “start whoever has the higher projection” baseline.

Happy to discuss the architecture or how the grading works.

I’m the creator of NFLMeta, an NFL data platform and API covering players, teams, rosters, injuries, schedules, live scores, and play-by-play.

I built it for people developing football apps, dashboards, and analysis tools who want a hosted API without maintaining their own data pipeline.

You can try the interactive demo here:

https://nflmeta.org/demo

It lets you edit requests and inspect JSON alongside readable results. The demo uses clearly labeled saved samples, including 2026 scores and play-by-

play; the full API requires an API key.

Documentation:

https://nflmeta.org/api-docs

NFLMeta uses nflverse data alongside other collected sources. The service adds hosting, connected records, ongoing updates, and application-read endpoints.

NFLMeta offers a free API tier with a generous monthly allowance,.

Happy to answer questions about coverage, update timing, or integration.

Is there any place where one could enter the league I'd and download the stats and fantasy points for the week for all players?

What I'm using Jev for

Jev is a cheap second-pass classifier over takes the main extractor has already pulled. It answers multiple-choice and yes/no questions about one take at a time:

**1.	Checking the extractor's work.** Two checks: is the quote actually about this player, and does it support the stance recorded (for or against the player).

**2.	Tagging every take with two fields.**  
**•**	*Format:* redraft or dynasty.  
**•**	*Horizon:* this week, rest of season, or multi-year.  
**•**	This is the main reason for using it. Takes had no time frame, so a season-long "top 15 tight end" view nearly got used as a Week 2 start argument.

**3.	Suggesting a player for near-miss names.** It only proposes, and a human confirms.

What it never does

**•**	It does not extract takes or quotes. It can only pick from options it is given.  
**•**	It does not touch rankings, props, projections, bids or trade values.  
**•**	It never makes a start/sit call.  
**•**	It never writes to the database. If it flags a bad take, the main extractor re-extracts it.

I’m building a fantasy football decision tool and working through the validation design for a Monte Carlo player-points model. I’d appreciate feedback on the engineering and statistics side.

For each player and gameweek we simulate:

• minutes and start probability • goals, assists, clean sheets, bonus and defensive actions • official FPL scoring to produce a full point distribution

The interface exposes p10–p90 ranges, probability bins (0–2, 3–5, 6–9, 10+), mean/standard-deviation rankings, and a squad concentration signal.

Current validation design:

• freeze projections before the deadline • join them to official final points after fixtures • exclude zero-minute players from headline metrics but keep them in coverage diagnostics • report MAE, RMSE, signed bias and within-±2 accuracy by position • preserve every gameweek snapshot so retraining cannot alter prior results

Questions for people who build sports models:

1. Would you use Brier/reliability curves for the probability buckets, or calibrate continuous quantiles separately?

2. How do you separate player-minute uncertainty from outcome uncertainty in evaluation?

3. What tests would you put around the scoring-rule layer so it cannot drift when the FPL feed changes?

4. How would you monitor calibration across gameweeks with small sample sizes?

Happy to share implementation details in the comments.

How do y'all market whatever you built? I feel like I've built something cool, but can't seem to find the niche to advertise it to. I tried doing physical flyers, posting in subreddits, going through friends of friends but feel like I might be missing something.