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How Pi Shot works

π is hiding between two well-chosen dates. Here's the trick.

The two anchor points

Pi Season is bracketed by two famous π approximations — one below the true value, one above:

DateValueNotes
March 143.14π rounded down to 2 dp
July 2222 ⁄ 7 = 3.142857142857…the classical fraction, π from above

Since 3.14 < π < 22⁄7, a straight line between these two points must cross π exactly once on the way up.

The interpolation

At any UTC instant t between the two dates, the formula is just linear interpolation:

piValue = 3.14 + (22⁄7 − 3.14) × t

where t is the fraction of the way from March 14 00:00 UTC to July 22 00:00 UTC. t = 0 puts you on 3.14; t = 1 puts you on 22⁄7.

Solving for the Pi Moment

Setting piValue = π and rearranging:

t = (π − 3.14) / (22⁄7 − 3.14) ≈ 0.5574287656…

So the Pi Moment is about 55.74% of the way through Pi Season. The full interval is 130 days = 11,232,000,000 ms.

Multiplying out gives 72 days, 11 hours, 10 minutes and ~38 seconds past midnight UTC on March 14 — which lands on:

Why some digits go green and some go red

The score is the number of decimal places where your piValue matches the true π. Each tenfold improvement in your timing buys one more matched decimal:

How close|value − π|Matched dp
~4 days off ~10⁻⁴4
~10 hours off ~10⁻⁵5
~1 hour off ~10⁻⁶6
~6 minutes off ~10⁻⁷7
~30 seconds off ~10⁻⁸8
~3 seconds off ~10⁻⁹9

With millisecond-resolution timing the theoretical ceiling is around 12 matched decimal places. The green digits are what you got right; the red digits are where your value diverged from π. Example for a shot fired about 30 seconds before the Pi Moment:

The catch

The server stamps your shot the instant the click arrives. Your computer's clock doesn't matter. Your latency to the server does — that's why the hunt has nerve in it.
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