How should I use this tool?

You should look at the top suggestions and decide for yourself which hero you think works better.
You should pick the role that your team needs and think about the lane that you will go to.
The picker can help you go outside of your comfort zone picking heroes you wouldn't normally consider, but advanced knowledge about the picked hero is definitely recommended.
Even if you are using a picker it doesn't mean that you should pick last (you may want to leave that for your mid or carry so that they don't get countered).
Try to analyze why certain heroes work better in certain lineups, even if you do this after the game has ended. It will make you a better player.

Drafting and picking is a huge part of Dota 2. This tool will help you when making decisions, but you should also use your own judgement.

How do you calculate the suggestions?

The suggestions are calculated statistically and are based on millions of games.
There are two modes used for suggestions, each with its own benefits. You can:

• Use advantages instead of winrates. This will favor a broader drafting pool of heroes and not only the most OP heroes in the current meta. It's very good for learning / playing varied heroes in the best conditions they can possibly be played (Advantage Scores Mode).
• Use winrates instead of advantages. This will favor the most OP heroes in the current meta and give an increased chance of winning (Winrate Scores Mode).

What other features are included in the app?

• Charts and Bonus Points, which vary throughout the game, can be shown and used with the suggestions.
• Selectors can be used to only show suggestions for specific lanes or roles.
• Matchup tables help with win predictions.
• We have a premium service, offered for as low as 1$ / month.
• Bonus scores, which are added when calculating hero suggestions, and are based on how well you played lately with each of the heroes. This should make the picker "mold" around your play style.

How often is this tool updated?

We usually update our data every week. It takes a while when a new patch comes, as a day or two of gameplay do not produce a large enough sample to make accurate suggestions.

Where do you take your data from?

The data is taken directly from Valve, who provide the Steam Web API.

I logged in, why don't you have my matches?

You need to expose your match data to third parties so that we can fetch it.

How to enable "Public Match Data":

• Open the Dota 2 game client and click on the "Settings" icon
• Navigate to "Options"
• Check the box to "Expose Public Match Data"

Why do you require the steam username and password when logging in?

We don't. You're entering the username and password on Steam's website.
We are using Steam OpenID - this allows our application to authenticate a user's SteamID without requiring them to enter their Steam username or password on our site. We never know your password. It's safe and officially supported.