One-Space Jump in Go — Ikken-tobi Explained | PlayGo.gg

When a stone placed has a line between itself and another stone.

What is a one-space jump?

An ikken-tobi is a stone played exactly one empty point away from a friendly stone along a row or column. The two stones aren't physically connected — there's a gap — but the gap is so narrow that a wedge into it gets ataried immediately. That's why ikken-tobi is treated as a virtual connection.

The Japanese proverb says "the one-space jump is never bad" — ikken-tobi ni akushu nashi. It's not literally true in every position, but the lesson is sound: when in doubt, ikken-tobi is the safe default. It develops faster than a solid extension and is far harder to attack than a knight's move or a two-space jump.

When to use a one-space jump?

Reach for ikken-tobi in four common situations:

- Escaping a weak group toward the center. A jump from a stone under attack runs into open space without offering a cuttable shape — the most common use. - Building a moyo with safety. When you want to add height to a framework, ikken-tobi extends your wall upward without weaknesses. - Pressing on an opponent's group. Jumping out from your own strength, one space at a time, keeps maximum pressure while denying the enemy a base. - Reinforcing after a contact fight. After a hane or cross-cut resolves, an ikken-tobi often consolidates the resulting shape.

The rule of thumb against the two-space jump (nikken-tobi): jump two when you're strong and the area is open; jump one when you're weak or under pressure. The two-space jump is faster but a wedge has three points to maneuver in, so it can actually be cut.

Example of a one-space jump in a game

Which moves qualify as a one space jump off of the G7 stone?

If you're a beginner unsure how to develop a stone toward the center, the one-space jump is the move you should reach for first. The proverb exists for a reason.