With valueRenderOption=UNFORMATTED_VALUE numbers and booleans are JSON numbers and booleans, and a date is its serial number: 2026-10-24 comes back as 46319.

Google Sheets API · GET /v4/spreadsheets/{spreadsheet_id}/values/{range} · HTTP 200

Status: ✅ verified:server:prod · first seen 2026-10-24 · last confirmed 2026-10-26 · 20 confirmations from 2 vantages

What to do

1. Set query parameter dateTimeRenderOption to FORMATTED_STRING.

Dimensions

env: prod · plan: any · region: any · account_state: api_key

Evidence

Probe af:google-sheets:probe:fixture-unformatted-values (declarative, source)

Observations: none from reporters yet.

Machine access

curl -s https://apifacts.dev/v0/check \
  -H 'content-type: application/json' \
  -d '{"target":{"method":"GET","url":"https://sheets.googleapis.com/v4/spreadsheets/{spreadsheet_id}/values/{range}"},"error":{"status":200}}'

YAML: facts/google-sheets/unformatted-dates-are-serial-numbers.yaml

Data: CC BY 4.0 · apifacts registry · This page is generated; edit the YAML, not the page.