Editorial policy

King to Ace publishes free solitaire games and guides about rules, strategy, odds and history. This page explains how those guides are made and what to do if you find an error.

How guides are written

• Written for players. Each guide sets out to answer a question players actually ask, with worked examples on real deals where we can. Guides are published under the King to Ace editorial team byline.
• Checked against our games. Rules, scoring values and settings described in a guide are checked against the code of the game on this site. Where other sites or apps use different rules, we say so.
• Sources for history and research. Dates, names and research figures are checked against published sources, and we name the source in the article. Popular stories that can't be confirmed (such as how Klondike got its name) are labeled as legends, not facts.
• No health or money promises. Articles about solitaire and wellbeing describe general information only and are not medical advice.

How we measure the odds

Win rates in our guides come from our own solver, the same program that powers the Hint button and picks the winnable deals in our games. The full method is in our odds guide. In short:

• The solver plays numbered deals from our games. In Klondike and Spider it can see the face-down cards, so it answers whether a winning line exists, not how often a person would find it.
• Each deal gets a fixed search budget, counted in positions rather than seconds, so the results are repeatable. Deals that run out of budget are reported as undecided, never counted as wins or losses.
• Every winning line is replayed through the game's rules to check it before it is counted.
• We report the number of deals tested next to every percentage, and we say when a figure is a lower bound.

Difficulty ratings and typical playing times in comparison tables are editorial judgment, and we label them that way.

Updates

When we change a guide in a way that matters (a corrected fact, new numbers, a rule change in one of our games), we update the date shown under its title.

Advertising

The site may show ads to cover its costs. Advertisers have no say in what we write, and we do not publish paid or sponsored guides.

Corrections

Found a mistake, an outdated rule or a claim you think is wrong? Email hello@kingtoace.com with the page address and what needs fixing. If it is a game problem, the deal number from the toolbar helps. We read every message and correct confirmed errors as soon as we can.

More about us is on the About page.