How it is checked
The dates each count is verified against, and the checksum of each algorithm.
The control dates
| Count | Date | What it must give | Status |
|---|---|---|---|
| Meza | 30 abr 1981 | 9 Itzcuintli · Tozoztontli · año 8 Calli | passes |
| Meza | 16 sep 1810 | 13 Atl · Xocotlhuetzi · año 6 Tochtli | passes |
| Meza | 7 ene 2016 | 8 Ehecatl · Atemoztli · año 3 Ácatl | passes |
| Meza | 22 may 2023 | 6 Malinalli · Ueitozoztli · año 11 Ácatl | passes |
| Meza | 10 mar 2001 | cuarto nemontemi · Nemontemi · año 1 Técpatl | passes |
| Caso (academic) | 8 de noviembre de 1519 juliano | 7 Cipactli | passes |
| Caso (academic) | 13 de agosto de 1521 juliano | 1 Cóatl | passes |
| González Cortés | 8 de noviembre de 1519 juliano | 8 Ehécatl | passes |
| Casa Moctezuma | 2 de marzo de 2025 | 3 Tochtli · año 12 Técpatl | passes |
| Casa Moctezuma | 19 de abril de 2026 | 13 Cipactli · trecena 1 Atl · año 1 Tochtli | passes |
Every count declares the dates it is checked against: two documented anchors for each academic correlation, and the five exercises the Meza book itself works through step by step, including the one that falls in the nemontemi.
If one of them stopped matching, publication would stop before the page did. Publishing the algorithm is a claim; publishing what verifies it is a demonstration.
Independent check
Publishing an algorithm is only worth something if the calculation can be redone with it. So it was redone: a from-scratch reimplementation, in another language, reading only what this site publishes and without opening the app's source.
The published formula is enough to hit a Julian date from 1519 and two Gregorian ones from 2025 and 2026. The published algorithm is complete. The Meza count was reimplemented the same way, from its five published steps, and hits all five of its control dates.
- 8 de noviembre de 1519 juliano expected «7 Cipactli» · reimplemented «7 Cipactli»
- 13 de agosto de 1521 juliano expected «1 Cóatl» · reimplemented «1 Cóatl»
- 8 de noviembre de 1519 juliano expected «8 Ehécatl» · reimplemented «8 Ehécatl»
- 2 de marzo de 2025 expected «3 Tochtli · año 12 Técpatl» · reimplemented «3 Tochtli»
- 19 de abril de 2026 expected «13 Cipactli · trecena 1 Atl · año 1 Tochtli» · reimplemented «13 Cipactli»
Where each algorithm lives
The algorithms live outside the code, in files of their own and sealed, so that they outlive the app and so that whoever inherits them knows what to implement. They are not distributed.
| Algorithm | Size |
|---|---|
| Meza | 6291 bytes |
| Caso (academic) | 4134 bytes |
| González Cortés | 4120 bytes |
| Casa Moctezuma | 4792 bytes |
How to cite this page
Alma Mexica, «How it is checked», En español. Revised 2026-09-17. https://almamexica.org/en/counts/proof/