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"publishedAt": "2026-06-29T09:41:35.000Z",
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"How to Fix Excel CSV Date Import Problems",
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"textContent": "You export a CSV from a UK system and double-click it in US Excel — `28/05/2026` suddenly looks like May 28, or something even stranger. The file isn't corrupt. **Excel is guessing your date format based on your computer's locale.**\n\nThis short guide covers why that happens, how to import CSV correctly, and how to batch-fix dates that are already wrong. For the full walkthrough with examples, see the official guide: How to Fix Excel CSV Date Import Problems.\n\n## Why Excel breaks CSV dates\n\nA CSV is plain text. It does **not** store whether a value is a date or a string. When you double-click to open, Excel parses using your regional settings:\n\n * US Excel: **MM/DD/YYYY**\n * UK / Europe: **DD/MM/YYYY**\n\n\n\nDates like `03/04/2025` are the most dangerous — both parts are ≤ 12. US Excel may read April 3; UK Excel reads March 4. **Excel won't warn you.**\n\nOther common traps:\n\n * Dates exported as **serial numbers** (e.g. `44927`)\n * Two-digit years triggering century guesses\n * Re-saving as CSV destroys formats a second time\n\n\n\n## The right way: don't double-click the CSV\n\n 1. **Open Excel first** — don't double-click the `.csv` file\n 2. **Data → Get Data from Text/CSV** (older Excel: Data → From Text)\n 3. Set date columns to **Text** if you need to preserve the original string\n 4. Confirm the source region (US / UK), then convert to a single format\n\n\n\nFor team data exchange, agree on **ISO 8601:`YYYY-MM-DD`** in your schema — unambiguous, sorts correctly as text, and works in JSON APIs and databases.\n\nAmbiguous value | US reads as | UK reads as | Safe format (ISO)\n---|---|---|---\n03/04/2025 | 2025-04-03 | 2025-03-04 | Confirm source region\n28/05/2026 | — | 2026-05-28 | 2026-05-28\n05/28/2026 | 2026-05-28 | — | 2026-05-28\n\n## Already broken? Fix dates in the browser (no server upload)\n\nI built a free tool cluster on FormatList — **everything runs locally in your browser** :\n\n### 1. Date Format Fixer — bulk repair\n\n * Paste a date column or upload `.csv` / `.txt`\n * Ambiguous rows highlighted; optional US / UK preference\n * Export **ISO / US / UK** or download a fixed CSV\n\n\n\nBest for: normalizing a whole column to ISO before a database or API import.\n\n### 2. Ambiguous Date Checker — check before you commit\n\nEnter a single date like `03/04/2025` and see **US vs UK interpretations side by side** — no guessing.\n\nBest for: visa forms, contracts, anything where the exact day matters.\n\n### 3. UK Date to US Date — DD/MM → MM/DD\n\nLock **DD/MM input → MM/DD output**. Batch-convert UK invoices or CRM exports for US systems.\n\n### 4. Fixed dates before JSON?\n\nNormalize dates to ISO first, then use CSV to JSON. **Order matters** — wrong dates baked into JSON propagate through your entire pipeline.\n\n## Quick FAQ\n\n**Q: Why did my dates turn into numbers like 44927?**\n\nA: Excel stores dates as serial numbers internally. Date Format Fixer converts them back to readable dates.\n\n**Q: Fix dates first, or convert to JSON first?**\n\nA: **Fix dates first.** Bad dates in JSON pollute validation and reporting downstream.\n\n## Summary\n\nScenario | What to do\n---|---\nNot imported yet | Excel \"import from text\"; set date column to Text or ISO\nTeam data exchange | Agree on `YYYY-MM-DD`\nAlready wrong | Date Format Fixer + manual review of ambiguous rows\nSingle date unclear | Ambiguous Date Checker\n\nIf you also work with ChatGPT output, JSON, or CSV pipelines, FormatList has JSON Repair, CSV converters, and more at formatlist.com.\n\n_Free tools, 100% browser-local. Feedback welcome on About._",
"title": "How to Fix Excel CSV Date Import Problems (US / UK Format Guide)"
}