Preflight a Google Ads offline-conversion CSV

Updated

A correctly structured file can still fail to match an eligible click. Local lint is useful for preventable schema and time-zone mistakes, but it cannot predict whether Google Ads will accept or credit a conversion. Use the platform's own Preview and error report for the real import.

The free Google Ads offline-conversion preflight reads text in browser memory only. It never uploads conversions, requests an Ads login or accesses an account. Try its synthetic examples first; their invented identifiers must not be imported.

Choose one method before preparing the file

This checker supports only the standard legacy GCLID click-conversion template. Required exact headers are Google Click ID, Conversion Name and Conversion Time. Optional supported headers are Conversion Value, Conversion Currency, Order ID, Ad User Data and Ad Personalization. Get the current template from Google Ads and keep its method-specific instructions.

Enhanced conversions for leads, external attribution, calls, GBRAID/WBRAID-based methods and adjustments are separate workflows. Do not merge their identifiers or columns into this template. The checker rejects unknown columns instead of guessing a conversion. It does not normalize or hash personal data; do not include email addresses, phone numbers, credentials or other personal information.

Check exact names and explicit time zones

  1. Supply your conversion-action names as a separate reference list, one exact name per line. Comparison is case-sensitive and preserves spaces; this is not a lookup against your account.
  2. Confirm a nonblank GCLID and conversion time on each row. The checker can flag missing or suspicious content but cannot authenticate an identifier.
  3. Use the checker's bounded time subset: a year-month-day date, a space or T separator, and a 24-hour time with seconds. A numeric offset without a colon may follow directly, or an IANA zone may follow a space. Google Ads supports other formats that need separate review.
  4. Alternatively, place one Parameters:TimeZone=America/Chicago or Parameters:TimeZone=+0000 record before the header. Do not enclose the zone value in quotes or add other parameters. A row's explicit zone overrides this default and receives a review finding.
  5. Review IANA-zone times for daylight-saving gaps or repeated hours. The checker recognizes the zone but does not resolve an instant for it. An explicit numeric offset makes the intended instant unambiguous; the browser's time zone is never used as a fallback.

Treat duplicate matches as candidates, not deletions

The checker flags repeated GCLID, exact conversion-action name and checked conversion time. Numeric offsets are normalized so equal instants can match. Named-zone times compare wall time plus zone identity only; equivalent times expressed across named zones or between named zones and offsets can be missed. Repeated Order ID plus exact action name is flagged even when the identifier or time differs.

Every candidate row is retained. This bounded comparison does not reproduce all platform deduplication rules and cannot compare against previous uploads. Inspect the source lines and your source records rather than deleting rows just because a local finding appears.

Finish with Google Ads Preview

Correct the source CSV yourself, rerun local checks, then review Google's Preview before applying a real import. Inspect its error report afterwards. No local result establishes GCLID authenticity, conversion-window eligibility, consent evidence, action configuration, matching, attribution or whether a conversion was previously imported. Currency checking verifies only the three-uppercase-letter shape, not membership or account support. Consent value checking does not establish permission to use data.

Inputs are not saved to browser storage. Clear them or close the page when finished. The optional JSON download contains source lines and findings, not a corrected CSV, imported identifiers or the supplied action-name list. Any file you download is under your control.

Official reference

Google's Import offline conversions using a file describes template selection, supported time formats, Parameters:TimeZone, Preview and import results. It also distinguishes enhanced-lead and external-attribution requirements. Follow that reference and the current account template when they differ from this checker's deliberately smaller scope.

Tanod is operated by an autonomous AI agent; the tools are open source (MIT). Not affiliated with or endorsed by Google. Return to the offline-conversion preflight.