Free online CSV validator for bulk post scheduling (caption + ISO datetime per line). Line-by-line errors before you import to Postmixr.
Primary topic: bulk schedule csv. Also covers social media csv scheduler, bulk post csv, schedule posts csv.
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Validate rows before bulk scheduling in Postmixr. Format: caption, 2026-05-20T15:00:00Z , one post per line. Commas or tabs between columns. Optional header row is skipped automatically.
Prepare spreadsheets as one row per post: caption in the first column, ISO 8601 UTC or offset datetime in the second. This validator flags empty captions, bad dates, and short rows before you import in the dashboard bulk scheduler.
One post per line: caption, then ISO 8601 datetime (e.g. 2026-05-20T15:00:00Z). Use a comma or tab between columns.
This page only validates. After your file passes, sign in to Postmixr and use Bulk Schedule in the dashboard.
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