The Three-Coin Method, Step by Step

The three-coin method is the most common way to consult the I Ching today. It is quick, needs nothing more than pocket change, and produces a full hexagram with changing lines in about a minute. This guide explains exactly how it works, so you can cast by hand or understand what our virtual coins are doing.

What you need

Three coins of the same kind. Traditional Chinese coins have a square hole and an inscribed side; any coins work.
A question, written down. (See How to ask a good question.)
Paper and pen, or our manual entry form.

Step 1: Decide which side is which

Assign a value to each face:

Heads (the inscribed or "yang" side) = 3
Tails = 2

Some traditions reverse this. What matters is that you choose one convention and keep it. Our site uses heads = 3, tails = 2.

Step 2: Toss six times

Hold the three coins, focus on the question, and let them fall. Add up the three values. The total is always one of four numbers:

Coins	Total	Line	Name	Changing?
2 + 2 + 2	6	broken, marked ✕	old yin	yes — becomes yang
3 + 2 + 2	7	solid	young yang	no
3 + 3 + 2	8	broken	young yin	no
3 + 3 + 3	9	solid, marked ○	old yang	yes — becomes yin

Repeat six times. Each toss gives one line.

Step 3: Build from the bottom up

This is the step people most often get wrong. The first toss is the bottom line (line 1), and the sixth toss is the top line (line 6). A hexagram grows upward like a plant: the lower lines describe the beginning or foundation of a situation, the upper lines its outcome or the wider context.

Draw each line as you go, starting at the bottom of the page.

Step 4: Identify the primary hexagram

Ignore for a moment whether lines are changing. You now have six solid or broken lines. The lower three form one trigram, the upper three another. Together they identify one of the 64 hexagrams in the traditional King Wen order. Our hexagram library shows every figure.

Step 5: Find the relating hexagram

If any line totalled 6 or 9, it is changing. Flip each changing line to its opposite — old yin becomes yang, old yang becomes yin — and keep every other line the same. The new figure is the relating hexagram (之卦), which shows the direction the situation is moving. Read more in Changing lines and the relating hexagram.

If there are no 6s or 9s, there is no relating hexagram: the situation is comparatively settled.

A worked example

Suppose your six tosses (bottom to top) total 7, 8, 9, 7, 8, 8.

Lines: solid, broken, solid (changing), solid, broken, broken.
Lower trigram (lines 1–3): solid, broken, solid = Li, Fire.
Upper trigram (lines 4–6): solid, broken, broken = Zhen, Thunder.
Primary hexagram: Thunder over Fire = Hexagram 55, Abundance.
Line 3 is changing. Flip it to broken: lower trigram becomes solid, broken, broken = Zhen. Thunder over Thunder = Hexagram 51, The Arousing.

You would read Hexagram 55, then line 3 of Hexagram 55 carefully, and then Hexagram 51 as the direction of change.

The probabilities

With three fair coins, each total has a fixed chance:

6 (old yin): 1 in 8
7 (young yang): 3 in 8
8 (young yin): 3 in 8
9 (old yang): 1 in 8

The older yarrow-stalk method, described in the Great Commentary (Xici), produces different odds: old yin 1/16, old yang 3/16, young yang 5/16, young yin 7/16. In yarrow, changing yang lines are three times more common than changing yin lines; with coins they are equally common. Neither method is "correct". Coins became widespread because they are fast; yarrow is valued for its slow, meditative rhythm.

Our virtual cast uses the three-coin probabilities exactly.

Virtual coins or real ones?

Both are valid. A virtual toss uses a random number for each coin with the same 50/50 odds as a physical coin. Real coins add ritual and slowness, which many people find helps them stay with the question. If you prefer them, toss by hand and enter the results on our manual page — you will get the same full reading.