SQL2XLSTimestamp

A 90-minute fix for a 40-year Excel timestamp issue

This tool detects and formats SQL-style timestamps in Excel datasets.

Published 30th September 2025 to mark the 40th anniversary of Excel's release.

Version 1.0

Features

• Detects parsed timestamps (even when Excel hides them as decimals)
• Formats columns as dd/mm/yyyy hh:mm
• Regex-based detection of time-only cells (e.g. 00:00.0, 12:30.5)
• Embedded calendar icon and tooltip for ribbon clarity
• Three interfaces:
  • .xltm for fast paste-and-format workflows
  • .xlsm with a ribbon button for manual control
  • .xlam add-in for global availability across Excel

Usage

1. Open Book.xltm and paste your dataset
2. Or open Book.xlsm and click SQL2XLS → Format Timestamps
3. Or install SQL2XLSTimestamp.xlam via Excel Add-ins for global access

Origin

Manufacturers and financial traders often use SQL databases with yyyy-mm-dd hh:mm:ss timestamps. When pasted into Excel, these can appear as decimals (e.g., 44561.5 for 2022-01-01 12:00:00) and are formatted as Time. To fix, the user must select the columns, format cells, open custom, and scroll to the bottom to select the timestamp format—every time.

This tool automates the detection and formatting of such timestamps.

License

MIT