Help Center

Start here — from the site's file to uploadable lineups

The whole loop in nine steps: pick your slate, build, download our CSV, upload it to the site.

Martian Flow Fantasy Sports sits between you and the contest site. The site gives you a player file; we turn it into a portfolio of legal lineups; you take our file back to the site. Nothing here enters contests for you, and nothing here needs your DraftKings or FanDuel password.

Quick start — your first set of lineups

Eight steps from opening the app to a file you can upload to DraftKings or FanDuel.

If you do nothing else in this Help Center, do this. It takes about two minutes of clicking and one build.

Just Pick For Me

What the automatic mode does, why two builds of the same slate differ, and when to take over yourself.

Just Pick For Me makes every decision you did not make. You give it a slate, a lineup count and any rules you insist on; it chooses the strategy blend, the exposure aims, the stacking mix, how much salary to leave on the table, and how far to lean away from the crowd.

It is deliberately random, and that is the feature

A tournament portfolio is not one answer. It is a purchase of many plausible ways the slate could break. So Just Pick For Me draws a fresh random seed on every build and uses it to pick one reading of the slate from a range of readings the evidence supports — how much to weight ceiling over median, how much to fade the chalk, which quarterbacks to spread across, how widely to spread the Captain or MVP seat.

The seed

The seed is just a number that fixes every random choice in the build. It is shown with your results. Two things follow: the same seed with the same slate and the same rules rebuilds the identical portfolio, and a different seed gives you a different one. You can pin a seed under Advanced settings if you want to reproduce a build exactly; leave it blank (the default) to get a fresh one each time.

Why it does not just play the highest projections 150 times

Because that portfolio loses. If you build the highest-projected lineup 150 times you own one opinion of the slate, and 150 copies of a wrong opinion is worth exactly as much as one copy. Worse, the highest-projected players are the ones everybody else also rosters, so the lineups that do hit are shared with thousands of other entries. A portfolio’s job in a large field is to be right in more ways, not to be identical and confident.

Conservative, Balanced and Aggressive

What each strategy actually changes about the lineups you get. No marketing — the real differences.

The three named strategies change what the optimizer considers valuable. They never change the rules. Every strategy obeys your locks, exclusions and exposure numbers identically, and every strategy produces legal lineups. The difference is entirely in what it is trying to maximise and how much repetition it tolerates.

What the exposure difference looks like

The clearest way to tell them apart is the Exposure tab. On the same 150-lineup Classic slate with no rules of your own, the highest-used player can run up to about 85% under Conservative, sits at or below a third under Balanced, and lower still under Aggressive. Aggressive spreads across more distinct players; Conservative uses fewer players more heavily.

Player controls — lock, exclude, min, max, exact

The five per-player rules, step by step, plus what happens when two rules disagree.

These are hard rules. Not preferences, not nudges — if the optimizer cannot satisfy one it fails the build and tells you which rules disagree. It will never quietly give you 68 lineups when you asked for exactly 70.

Lock and Exclude — the fast path

Minimum, maximum and exact exposure

How a percentage becomes a number of lineups

Percentages rarely divide evenly, so the conversion is fixed and stated rather than left to chance. A minimum rounds up, a maximum rounds down, and an exact percentage rounds to the nearest whole lineup (with a half rounding up). An explicit lineup count is used exactly as typed and overrides any percentage.

Editing and removing rules

When rules conflict

Your rules are checked before any lineups are built. If two of them cannot both be true, the build refuses and the message names the players and the rules involved. Nothing is silently weakened, reinterpreted or dropped — the fix is always yours to choose.

Salary — the cap, the floor, and why lineups leave money unspent

The site's cap is always enforced; Min and Max salary used are yours; leaving salary on the table is often deliberate.

Captain and MVP controls

The premium seat on DraftKings Showdown and FanDuel Single Game: locking it, capping it, and how it relates to overall exposure.

Single-game rosters have one special seat. DraftKings calls it the Captain (CPT); FanDuel calls it the MVP. The app always uses whichever word your site uses. On both sites that player scores 1.5× fantasy points and costs 1.5× salary.

The two exposures are different numbers

Overall exposure counts every lineup a player appears in, in any seat. Captain/MVP exposure counts only the lineups where he holds the premium seat. Captain appearances are part of overall exposure, not extra to it.

Setting them

Stacking

Correlated lineups: QB+1, QB+2, QB+3, bring-backs, and how stack rules interact with exposure rules.

A stack is a group of players whose scoring is connected. The classic one is a quarterback with his own pass catchers: when the quarterback throws a touchdown, one of his receivers caught it. One real play, points in two roster spots.

Why correlation matters in tournaments

In a large field you are not trying to score well on average, you are trying to finish first. Correlated lineups have fatter tails: when the game you stacked goes the way you bet, several of your roster spots go off together and the lineup lands near the top rather than merely above average. The cost is the other side of the same coin — when that game is a dud, more of your lineup is dead at once. That trade is the point, and it is why stacking is standard in tournaments and much less common in cash games.

The Stacking section

Right under the player pool. Pick QB + 1 pass catcher, QB + 2 pass catchers, QB + pass catcher + bring-back or Custom (smallest and largest stack, bring-back, one team), then the share of builds. On a single game the choices are the single-game ones — QB + same-team pass catcher, QB MVP + 2 pass catchers, the offense you expect to lead, and MVP rotation (the strongest core with one lineup per MVP that has a real ceiling). Anything Gus sets appears here too, marked set by Gus. After the build, the Stacks tab of Portfolio Review shows each rule next to what you got. Martian Flow pairs quarterbacks with their receivers on its own even with nothing set; these controls are for requiring more.

Every other stack rule

How stack rules interact with exposure rules

Exposure — the number people ask about most

What exposure means, why the automatic build caps itself around a third, and why not every good player can be at 30%.

Exposure is simply how many of your lineups contain a player, usually shown as a percentage. If a receiver is in 15 of your 150 lineups, his exposure is 10%. 50 of 150 is 33%. 150 of 150 is 100%, which is what a Lock does.

The organic ceiling: about one-third

On Classic slates, Balanced and Just Pick For Me will not organically put a player you have not ruled on into more than one third of your lineups — 50 of 150, 33 of 100, 6 of 20. Not “usually”, and not as a soft preference. It is a ceiling, and it exists because a portfolio that pours one player into 90% of its lineups is not a portfolio: it is one bet with 150 receipts, and it loses in exactly the way a portfolio is supposed to protect you from.

Conservative deliberately sits above this — riding your best plays hard is that strategy’s whole identity and you choose it by name — and Aggressive deliberately sits below it.

Why single game is different

A single-game slate has one game in it. Six roster seats must be filled from two teams, so there are only so many players available, and high overall exposure is sometimes simply arithmetic rather than a preference. The build still aims for a third. When the usable pool genuinely cannot support that — there are not enough quality players to fill six seats per lineup with nobody above a third — it raises the cap to the lowest value that is actually achievable, and says so in the build notes. It never removes the cap. “We could not do a third” is never allowed to become “anything goes”.

Why not every good player can be at 30%

Because a lineup has a fixed number of seats. In 150 DraftKings Classic lineups there are 1,350 roster spots in total, and only 150 of them are quarterback seats. If you want ten quarterbacks in your portfolio they average 15% each, and no amount of liking all ten changes that. The same arithmetic applies at every position. Exposure is a budget, and the budget is set by the roster, not by the optimizer’s opinion.

The low-exposure tail

A large automatic build will show a long tail of players at 1–3%. That is intended. In 150 lineups, one lineup is two-thirds of one percent of your portfolio — a cheap shot at a big outcome that costs almost nothing and pays enormously if it lands. A portfolio with no tail at all has quietly become 150 versions of the same opinion.

The build charges itself for token exposure that has no justification, so a player with no price advantage, no ceiling and no leverage does not get a free single appearance. But it never adds a blanket minimum exposure to make the numbers look tidy: a player worth rostering gets a cluster, and one who is not gets zero.

Pair exposure: how often two players appear together

Exposure on a single player says nothing about who he appears with. Two backs from the same team can each sit at 40% and still never share a lineup, because the build had no reason to construct one that way and nothing asked it to. Pair exposure is where you ask. Under Advanced rules, pick two players and choose Never together, At most, At least or Exactly, then a percentage.

The percentage is a share of your whole portfolio, not of either player’s own lineups. On 147 lineups, “at least 5%” and “at most 12%” together mean between 8 and 17 lineups contain both of them — a minimum always rounds up and a maximum always rounds down, and the control shows you the whole number beside the percentage before you save it.

Projections, ownership, value and Sleeper Score

Every column in the player pool: where the number comes from and what it does not claim.

Some of these numbers come from the file you imported. Others are calculated here. The difference matters, so it is stated for each one, and nothing on this screen is ever invented to fill a gap — a missing number shows as —, not as a guess.

Sleeper Score

The Sleeper Score measures leverage: how much more the lineup mathematics wants a player than the field is expected to. It is not a ranking of who is best. A superb, universally-rostered player can score low simply because everybody already has him.

It is a weighted sum of named components, and clicking any score opens the full breakdown with each component, its weight and its raw figures, so you can recompute it by hand if you want to. There is no black box and no “our model likes him”. Quality is established first, from evidence unrelated to ownership — low ownership only counts in a player’s favour after he has cleared that bar, so a bad player never becomes a sleeper by being unpopular.

Ownership — an estimate of the field, not a fact

What projected ownership is, where it comes from, why it is never a known number, and how the build uses it.

Projection is an estimate of how many fantasy points a player scores. Ownership is an estimate of how much of the contest field will roster him. They are different questions, and a player can be high on one and low on the other — that gap is what tournament players call leverage.

Injury status

What Q, D, O, IR and NA mean here, which players are excluded automatically, and the one thing you must still do yourself.

Injury designations come straight from the player list you imported. Nothing is scraped, guessed or filled in — where the file carries no status, no badge is shown.

Hover any badge to see the full word, plus the body-part detail where your file carries one — FanDuel player lists include an injury-details column, DraftKings salary files do not, so you will see detail on FanDuel slates and usually not on DraftKings ones. Opening a player’s panel shows the same detail inline next to his name.

DraftKings vs FanDuel

The differences that actually change your lineups, as this product implements them.

The consequences worth knowing: FanDuel’s higher cap and 4-per-team limit make heavy single-team stacks harder to fit, and its three-team minimum rules out two-game lineups entirely. DraftKings’ two-game minimum is the looser constraint, so DraftKings Classic portfolios can concentrate on fewer games.

Classic vs Single Game

Why single-game portfolios look so much more concentrated, and what to look at instead.

Why single game concentrates more

It is arithmetic, not a change of philosophy. Six seats × 150 lineups is 900 roster spots to fill from one game’s worth of players. When only a dozen or so are genuinely worth rostering, each of them has to carry a large share of those 900 spots — there is nowhere else for the seats to go. An elite player at 50–65% overall exposure in a single-game portfolio can be entirely correct, while the same figure on a Classic slate would be a red flag.

So on a single-game slate, judge the portfolio by the Captain/MVP spread rather than by overall exposure. That is the seat that actually differentiates your lineups, and it is where the build spends its diversification effort.

Getting a slate in, and getting your lineups out

Which files to download from the site, how to import them, how to export, and what the errors mean.

Getting a slate in

If the slate you want is already listed under Pick a slate, you are done — select it and carry on. Otherwise you can bring one in yourself from the site’s own export.

Getting your lineups out

What the import messages mean

DraftKings Classic — file in, lineups out

The DKSalaries.csv in, the site's entries-format CSV out, and back to DraftKings.

DraftKings Showdown (Single Game) — file in, lineups out

The Showdown salaries file in, a CPT + FLEX CSV out, and back to DraftKings.

FanDuel Main Slate — file in, lineups out

The FanDuel players list in, the lineup-upload template layout out, and back to FanDuel.

FanDuel Single Game — file in, lineups out

The Single Game players list in, an MVP + FLEX CSV out, and what FanDuel's own template says about it.

Reading your build results

Every number and tab on the results screen, and which ones are worth acting on.

The summary numbers

The tabs

The diversity numbers

Portfolio Review

Below your results, Portfolio Review opens on a Summary of what you got: requested against generated lineups, every player's exposure with the Captain/MVP and FLEX seats split out, which of your ceilings were reached, whether every floor, lock and exclusion was met, how many players any two lineups share, where the salary went, how the portfolio stacks, and anything unusual. The review knows which mode built the portfolio: a Custom Strategy build is measured against your own rules, and Conservative, Balanced and Aggressive are never mentioned as the reason for a frequency they did not set. The other tabs are an analytical comparison with a neutral, projection-only read of the slate — worth a look, never a verdict, and a player sitting below an at-most ceiling is never flagged for it. It only reports — it never changes your lineups.

Saved builds, comparing, and rebuilding

Keeping a portfolio, comparing two of them, and the difference between freezing and locking.

Freeze is not lock

These two sit near each other and mean unrelated things. Freezing a lineup keeps that lineup exactly as it is while you rebuild others; it says nothing about where those players appear elsewhere. Locking a player puts that player in every lineup; it says nothing about any lineup staying put.

How long a build takes

Why 150 lineups is not 150 small problems, what the progress messages mean, and the time limits.

Building 150 lineups is not 150 separate jobs. The whole set is balanced at once — exposures kept sensible across the portfolio, lineups kept genuinely different from one another, every rule of yours satisfied by the set rather than by each lineup individually. That coordination is the product, and it is what takes the time.

While it runs, the button reports the stage it is in and how long it has been going — preparing the player pool, generating lineups, choosing the portfolio, applying your rules, improving it, validating, finishing. Those are real stages, reported as they happen; there is no fake percentage bar counting up to a number nobody knows.

The time limit

Ordinary builds are held to about three minutes. When that budget runs out, the optional improvement work stops and you are given the best complete, fully-validated portfolio found so far — and a message at the top of your results says that refinement was cut short. What the clock can never do is hand you something partial: it cannot skip validation, break a rule of yours, produce duplicate lineups, or return fewer lineups than you asked for. If no complete legal portfolio has been found at all, the build fails and says so rather than inventing one.

Troubleshooting

The failures people actually hit, and what to change.

Account, subscription and billing

Trial, payment, cancelling, password, and partner codes.

Responsible play, and what this product does not claim

Plain statements about risk, predictions, ownership and affiliation.

Glossary

The vocabulary, in one place.