When to use a probe guess

A probe is a guess you play to learn something, knowing it cannot be the answer on the board you are trying to solve. It costs a guess now in exchange for fewer wasted guesses later.

A worked example: the -IGHT trap

This is a constructed example. Suppose one board has turned into _IGHT, with four greens in place. Quordle's answer list contains nine words that fit:

EIGHT, FIGHT, LIGHT, MIGHT, NIGHT, RIGHT, SIGHT, TIGHT, WIGHT

If you try them one at a time, you might need up to nine guesses for this board alone, which you do not have.

Now consider guessing FERNS, which cannot be the answer. Against those nine words it splits them like this:

Five of the nine possibilities are settled by that one guess. On average you are left with about 2.3 words instead of 9. And because FERNS is played on all four boards, it may help the other three as well.

When a probe is worth it

• Early and mid game. With six or seven guesses left and four boards open, one guess spent on information is often cheaper than several guesses spent on coin flips.
• When one board has a large family of near-identical words. Patterns like _IGHT, _ATCH or _OUND are classic traps.
• When the probe also helps other boards. A guess that splits two or three boards at once is especially valuable.

When it is not

• Near the end. With one or two guesses left, every guess should be a word that could solve a board. A probe that leaves you one guess short loses the game.
• When a board has only two candidates. Guessing one of them solves the board half the time and reveals the other otherwise, so a probe rarely helps.

Finding probes

The Quordle solver suggests next guesses and notes when a suggestion is "purely for information". You can also use the word finder with "Only words that can be Quordle answers" unticked to search every accepted guess for one that contains the letters you want to test.