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tshaddoxyesterday at 6:45 PM1 replyview on HN

It's a common source of off-by-one date formatting bugs in client-rendered web apps, particularly ones that pass around "YYYY-MM-DD" date strings (common for OpenAPI JSON APIs).

  const dateStringFromApiResponse = "2026-01-12";
  const date = new Date(dateStringFromApiResponse);
  const formatter = new Intl.DateTimeFormat('en-US', { dateStyle: 'long' });
  formatter.format(new Date("2026-01-12"));

  // 'January 11, 2026'

Replies

jazzyjacksonyesterday at 9:59 PM

I'm having flashbacks to writing Power Automate expressions to reconcile Dates passed from Outlook metadata to Excel

Basically just extracting numbers from string index or regex and rearranging them to a string Excel would recognize