# gregorian calendar

drillable.com › aa-usno-navy-mil › easter › gregorian calendar.
As of the index built 10 Sep 2026, 09:10 UTC · [cites, never asserts](/standing).
Source: The Date of Easter, by https://aa.usno.navy.mil.
MCP https://mcp.drillable.com · [html](/e/aa-usno-navy-mil/easter/gregorian-calendar.html) · [markdown](/e/aa-usno-navy-mil/easter/gregorian-calendar.md) · [json](/e/aa-usno-navy-mil/easter/gregorian-calendar.json) · [discovery](/.well-known/drillable.json) · [guide](/llms.txt)

## Records (8)

By drillable.com ([llm-extract/1](/standing#methods)); scored precision 1.00, recall 0.37 on the harness's last sample of 30.

- **agreement-with-tropical-year** = within a half a minute · [quote](/r/sha256:4a8ee6982c84b7f1a8d582d53ae4629e7d1a26263c65d783109a5a4c639a547b?trace&start=3915&end=3988) · [sha256:afb9fa05a4e4c15a…](/r/sha256:afb9fa05a4e4c15a26a93937a8ad24b8bc789cf33a306c887f85e140e8b0f1b2)
- **average-year-length** = 365.2425 days · [quote](/r/sha256:4a8ee6982c84b7f1a8d582d53ae4629e7d1a26263c65d783109a5a4c639a547b?trace&start=3845&end=3914) · [sha256:a4b6aa0e812cd146…](/r/sha256:a4b6aa0e812cd146297dd7e0d99088fa0caf476aef76c2bdc8d391291751dc8f)
- **date** = 1582 · [quote](/r/sha256:fc5da3e596d6bbf018d0c47277abfdda49c7f0ee9dd9f67a692ea3213a7b23f1?trace&start=3462&end=3601) · [sha256:0c17e6bbd7b39bbf…](/r/sha256:0c17e6bbd7b39bbf75031299415691897f5c8fddca1efc058be9022e4f99d77f)
- **drift-period** = 3300 years · [quote](/r/sha256:fc5da3e596d6bbf018d0c47277abfdda49c7f0ee9dd9f67a692ea3213a7b23f1?trace&start=3936&end=4047) · [sha256:1bd65be35a05669d…](/r/sha256:1bd65be35a05669d624265ddc626a6822c0c4dc1facecd7dc54233961b60407f)
- **length** = 365.2425 days · [quote](/r/sha256:fc5da3e596d6bbf018d0c47277abfdda49c7f0ee9dd9f67a692ea3213a7b23f1?trace&start=3796&end=3858) · [sha256:68aaf8ad05127fce…](/r/sha256:68aaf8ad05127fceec5c3419612b3c9e197c7dc1d5a55c574b51fcc9c7e47b29)
- **rule** = years evenly divisible by 4 are leap years, with the exception of centurial years that are not evenly divisible by 400 · [quote](/r/sha256:4a8ee6982c84b7f1a8d582d53ae4629e7d1a26263c65d783109a5a4c639a547b?trace&start=2063&end=2181) · [sha256:1660232bb6e2788e…](/r/sha256:1660232bb6e2788e657810ca8643c401e969076febe9dea3174f81ca8d7c5b68)
- **spring-alignment** = March 21 · [quote](/r/sha256:fc5da3e596d6bbf018d0c47277abfdda49c7f0ee9dd9f67a692ea3213a7b23f1?trace&start=3528&end=3601) · [sha256:a2ab762e4d828cc3…](/r/sha256:a2ab762e4d828cc3f97d1f61fb0380bedf875cb07aa1d0680d8d1b30fff5cf41)
- **drift-period** = 3300 years [superseded] · [quote](/r/sha256:4a8ee6982c84b7f1a8d582d53ae4629e7d1a26263c65d783109a5a4c639a547b?trace&start=3989&end=4100) · [sha256:4eb94f56b5d88042…](/r/sha256:4eb94f56b5d880422e5775d41809575656dfb143ade07da77474c22eb99af438)

Everything here is a record by a named reader, arranged; where readers disagree, both are shown.
No reader has asserted a label for it; the title is its address.

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