Diagnose timezone drift
Use this lab when timestamps look right in one tool but shift unexpectedly in another. The goal is to isolate whether the issue is source timezone, DST, or CSV interpretation.
- 1
Inspect the source timestamp format
Look at the raw input file in a plain text editor first. Determine whether the timestamps are timezone-aware (for example, include Z or +00:00) or whether they are naive local wall-clock timestamps.
- 2
Set the source timezone deliberately
In the Timezone Converter, choose the timezone that reflects how the original file should be interpreted, not just where the file came from organizationally.
- Denver in May should be treated as MDT, not MST.
- Timezone-aware ISO timestamps should already encode the source offset.
- 3
Convert to the target timezone
Choose the target timezone that your downstream tool or reporting workflow expects. Convert and then inspect the first few rows of the output file carefully.
- 4
Re-upload without spreadsheet reformatting
If you plan to upload the converted CSV into another GridMango tool, use the exported CSV directly. Avoid opening and resaving it through spreadsheet software first, because that can rewrite the timestamp format and shift interpretation.
- 5
Validate in the baseline preview
Upload the converted CSV into the baseline tool and confirm that the first timestamp shown in the preview matches the exact timestamp you expect from the conversion.
- If it does not match, inspect whether the timestamp is ISO-like or locale-like.
- Use this as your decision point before running any baseline analysis.