Simulator FAQ

What is THE SOLVER’s NFL DFS simulator and what does it do?

THE SOLVER NFL DFS simulator takesa lineup (or multiple lineups) and simulates them in a DraftKings/FanDuel contest, giving you a variety of info about the lineup, such as its expected ROI, mean and ceiling projections, cash rate, and more. The simulator also gives you a distribution of the lineup’s finishing position in the simulated contest.

What is the purpose of the simulator?

The purpose of the simulator is to use it as a tool for finding good NFL tournament lineups. The simulator won’t “spit out lineups for you”, it will instead give you information about lineups you submit. A good way to think about it is that you should “ask the simulator questions” you want answered for the slate.

For example:
Should I stack Jalen Hurts with 1 or 2 WRs? You can test a few versions of each and get a sense of which side has a better expected ROI. Alternatively, you can use our multi-lineup simulator to simulate 300 single stacks and 150 double stacks and then compare the expected ROI’s of those lineups.

Another example:
Should I include an opposing WR in my Patrick Mahomes stacks? Using the same methodology above, you can test lineups with and without WR “bring backs.” The opportunities to test are endless.

How much will this cost?

Option 1: A single lineup simulator. You can submit one lineup at a time. This costs $19.99 a month. We believe this product can fit in nearly every DFS player’s budget.

Option 2: You can submit up to 20 lineups at a time from THE SOLVER optimizer. This costs $39.99 a month. You will need a separate NFL optimizer subscription (or All Sports optimizer subscription) to be able to use this option.

Option 3: You can submit up to 300 lineups at a time from THE SOLVER optimizer. This costs $149.99 a month. You will need a separate NFL optimizer subscription (or All Sports optimizer subscription) to be able to use this option.

How does this work?

For background, this simulator was created in partnership with Establish The Run (ETR). To make a complex process as simple as possible, ETR is projecting the typical performance of every player, generating simulated “field” lineups that align with the types of teams expected to be entered into a given contest, and then simulating the results of NFL games to determine how each lineup would fare given realistic NFL play. Importantly, ETR has invested heavily into making sure the simulations are accounting for a variety of complex factors, including the correlation between players on the same team and in the same game. Other factors include Vegas totals, weather, teams play calling tendencies, opponents, schemes, and so on.

Using the above methodology, we then simulate the actual DFS tournament 10,000 times to ensure we have a significant sample size for you to analyze the results.

How can I trust the accuracy of these results?

It’s a great question, and to be honest, you’re probably just going to have to try it out and see what you think. But to provide more context, both The Solver and ETR have a significant track record in creating high-quality products for fantasy sports players. We have invested thousands of hours of effort into building this product. We don’t put our name on any product without believing it is up to our standards. As we get more data from our results in the 2023 NFL season and beyond, we’ll both make improvements to the product and hope to share more data about the accuracy of our work.

Do I need an ETR Subscription to use this product?

No. While the product is based in part on ETR analysis, no subscription to ETR or any other content provider is required to use it.

What slates does the simulator work with?

Currently we will only support DraftKings/FanDuel NFL classic main slates. We aim to add showdown and smaller slate support in the future.

What projections does the simulator use?

This product is tied to both ETR's player projections and simulated fields. The process that simulates both the NFL games and the DFS fields cannot be adjusted manually while retaining the same accuracy. We are evaluating future versions of the product that will provide more features.

How is the SIM ROI calculated? What does it represent?

The SIM ROI is calculated by summing up all of the prizes your lineup theoretically wins in our 10,000 simulations, divided by the required contest entry fees.

The SIM Cash Rate is how often the lineup finishes in a paying position in our 10,000 simulations.

Why do I get different results when submitting the same lineup multiple times?

We generate a number of different sets of field lineups as there is a significant amount of variance in which lineups will actually be entered into a contest given expectations on player ownership, contest structure, etc. This allows users to see how a lineup does among a variety of fields that are centered around the same ownership but a little bit different each time.

So, based on the field lineups in that specific run, the results will change slightly. If you want to use the same exact set of “field lineups” each time, you can select the checkbox “Use the same field as the previous Sim.”

We recognize this can be a little confusing, but one of our goals is to minimize the amount of false precision created by this product.

Why can’t I upload my own field lineups?

It is a difficult process to predict field lineups, on which a variety of factors will have an impact. We’ve invested heavily into solving this problem, and believe that we can do it better than anyone else, so we made the decision to design our simulator to work with our field lineups for now. This also allows us to make the simulator more affordable and faster.

Do you guarantee that I’ll win if I play lineups that show a positive ROI in the simulator?

No. It’s important to us that we’re honest about what we can and can’t do. We’re serious about creating high-quality tools and have spent our careers building our knowledge while earning the trust of our audience. We make no guarantees and do not claim to provide any sort of financial or investment advice. If you think it’s important that someone provides or implies some sort of guarantee about the results you will have using the service, you’re in the wrong place.

Where can I send feedback about the product?

You can send us feedback or questions about the product to

What is a good SIM ROI/SIM Cash Rate?

ROIs and cash rates will vary depending on the slate and tournament based on factors such as how chalky the best plays are and how good those plays are relative to their ownership.

In general, the ROIs and cash rates should be used to compare lineups to each other, instead of shooting for a specific number to reach. Some tips we have for tournaments are:

  • Use the tools to find the best CONSTRUCTION of lineups and to answer questions such as “Should I single or double stack Joe Burrow”? Should I run-back Joe Burrow stacks? How important is ceiling/projection relative to ownership?
  • If you think our projection is too low on Running Back A, lineups with that player may show a negative ROI, but you can still use the tool to find the best Running Back A lineup. The tool should be used in conjunction with your opinions/thoughts.
  • Make sure you have a relatively high finish percentage in the top 1% of the tournament. It’s probably best if the “highest bar” is the 1% bar. For example, we think the first finish position here is better than the second:



Can the Simulator be used for cash games?

We don’t recommend using the simulator for any cash game decisions, as the simulator specifically works with “field lineups” intended for the tournaments we are simulating. Cash games generally have entirely different lineups and we think anything from the tournament simulator will not be relevant to cash games.

Is there a tutorial on using the multi-lineup sim tool?