Chapter 11b — Zygalski Sheets

Zygalski Sheet Overlay Simulator

Watch perforated sheets narrow down the Grundstellung one female at a time. Each overlay eliminates impossible rotor positions until only the true setting remains.

The Zygalski sheet method exploits females — observable indicator patterns where the same letter appears at positions 1&4, 2&5, or 3&6 in the doubled message key. Each female means the characteristic permutation has a fixed point. By overlaying perforated sheets (one per female), the set of possible Grundstellungen shrinks until only one remains.
26 x 26 Candidate Grid Surviving: 676 / 676

Observed Females

Generate traffic to discover females...

Attack Progress

Current Step
--
Remaining
676
Last Elimination
--
Total Eliminated
0%
Search space narrowed:
Grundstellung Found
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Configuration

Rotor Order (known)
True Grundstellung (secret)
InstantFastMediumSlow
True settings hidden
Females (pos 1&4) --
Females (pos 2&5) --
Females (pos 3&6) --
Overlays applied 0