How do I trade down into a winning endgame?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws for movement, checkmate and both repetition rulings: a side that forces a repetition by perpetual check or perpetual chase loses rather than drawing. The chase half has not been validated against the official casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it before publishing.
Direct answer
Know where you are heading before the first trade, not after the last one. Simplifying is only useful if the material you are left with can actually force mate, so check the target endgame against the material table first, and only then start trading toward it.
The trap to avoid
Trading down to a lone cannon against a bare general, or a lone chariot against an intact defence, feels like winning material all the way and produces a draw at the end. Know the destination before beginning the journey.
What to trade and what to keep
Offer trades of the pieces you have in excess and keep the ones your target endgame needs, in line with the general trading advice in what to trade heading into an endgame. If you are heading for a chariot endgame, trading extra minor pieces while keeping chariots on is usually right; if you are heading for cannon and advisor, protect the advisor specifically.
Related questions
Should I always simplify when ahead on material?
Usually, but only into material that is actually winning. Check the table first.
What if I am not sure the resulting endgame wins?
Do not trade yet. Improve the position instead until the resulting material is clearly enough.
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