How to Preserve Microsecond Timestamps When Importing CSV into Excel
Question details
The user needs to prevent the application from truncating high-precision microsecond timestamps when importing a CSV file.
- Product
- Microsoft Excel
- Device & OS
- not provided
- Scenario
- Importing a CSV file containing date-time data that includes microsecond precision.
- Observed behavior
- The application automatically truncates or rounds the microsecond portion of timestamps (e.g., 2025-12-18 00:08:46.730845) upon opening or importing the CSV file.
Ensure your CSV file is saved locally and avoid opening it directly by double-clicking, as this triggers the default automatic formatting which destroys microsecond precision.
Use the Get Data Feature to Load Timestamps as Text
Importing the CSV via the Power Query editor allows you to define the column format as Text before the data is loaded, preserving the exact microsecond string.
Because spreadsheet applications natively store dates and times as serial numbers with a 15-significant-digit limit, any precision beyond milliseconds is automatically discarded. By forcing the import process to treat the column as plain text, you bypass this numerical limitation.
Navigate to the Data tab on the ribbon, select Get Data, choose From File, and click From Text/CSV.
Locate your CSV file containing the microsecond timestamps in the file browser and click Import.
In the preview window that appears, click Transform Data instead of clicking Load. This opens the Power Query Editor.
Click the data type icon (usually showing 'ABC' or '123') in the header of your timestamp column. Select Text from the dropdown menu, and if prompted, choose to Replace current.
Click Close & Load in the top left corner of the Power Query Editor to bring the preserved text data into your worksheet.
How to Safely Import CSV with Microseconds in WPS Office
WPS Spreadsheet features an intuitive Text Import Wizard that gives you full control over your data types, ensuring high-precision data like microsecond timestamps remain completely intact as text strings.
- 1. Open WPS Spreadsheet: Launch WPS Office and create a new blank spreadsheet.
- 2. Start the import wizard: Go to the Data tab, click Import Data, and select your target CSV file.
- 3. Configure import settings: Follow the wizard prompts until you reach the column data format step. Click on the column header that contains your microsecond timestamps.
- 4. Set format to Text: Change the Column data format option from General to Text to prevent precision loss, then click Finish.
Frequently Asked Questions
Why does Excel truncate my microsecond timestamps?
Excel stores dates and times as serial numbers, which are subject to a strict 15-significant-digit architectural limit. Any time resolution finer than milliseconds is automatically truncated or rounded when the system recognizes it as a date-time value.
Can custom cell formatting display microseconds?
No. The custom number format for time only supports up to milliseconds (using .000). Adding more zeros (like .000000) will not reveal microseconds because the underlying precision is permanently lost during the default import.
What happens if I just double-click the CSV file to open it?
If you double-click a CSV file, the software will automatically parse the data using its default General format settings. This immediately truncates your microsecond timestamps to milliseconds without giving you an opportunity to intervene.
How can I perform calculations on these text-based timestamps?
Since native date functions cannot process microsecond precision, you must either use string-manipulation functions (like LEFT, MID, or RIGHT) to extract the microseconds for separate math, or utilize a specialized programming tool like Python or pandas.
