Webclat / PostHog Practice

PostHog migration guides: one method, every source platform

Moving analytics onto PostHog is event-mapping and verification work, not a data export followed by hope. Here is the method we use, and the guides for each source platform.

The method, regardless of source platform

  1. Event and property mapping. Every event and property in the source platform gets a deliberate mapping decision in PostHog - not a blanket recreate. This is also where we apply the autocapture vs. explicit events framework, since a migration is the natural point to fix a taxonomy that drifted on the old platform.
  2. Parallel run. Both platforms track in production simultaneously for a defined window, so numbers can be reconciled before anyone trusts PostHog as the source of truth.
  3. Verification. Key funnels, retention curves, and dashboards get compared side by side. Discrepancies get root-caused - usually a mapping gap, not a PostHog limitation - before cutover.
  4. Cutover with a rollback path. The old platform stays reachable until the team is confident, not switched off on migration day.

Migration guides by source platform

FromGuideNotes
AmplitudeAmplitude to PostHog migration guideDedicated guide - we also run an Amplitude practice, so this direction is worked from both sides
MixpanelMixpanel to PostHog migration guideDedicated guide - narrower analytics-only scope usually simplifies mapping
Google Analytics / GA4Scoped per engagementOften a partial migration - see PostHog vs Google Analytics for how the split usually works
HeapScoped per engagementHeap's autocapture-heavy model needs a deliberate re-architecture, not a straight event copy

Why the migration guides exist even without search volume behind every direction

Search-volume research for this site found essentially no measured search demand for literal phrases like "amplitude to posthog migration" - a finding we label plainly rather than pretend otherwise. We build these guides anyway because the underlying questions get asked constantly in engineering conversations and to AI assistants, even when they don't show up as Google search volume yet. The method above is what we actually run regardless of how someone found this page.

Frequently Asked Questions

Which migration to PostHog is most common?

Amplitude and Mixpanel are the two directions we see most often, followed by GA4 (usually a partial migration - marketing attribution often stays on GA4 while product analytics moves to PostHog) and Heap.

Can PostHog import historical data from another platform?

Historical event data typically needs to be exported from the source platform and imported or backfilled into PostHog rather than a native one-click import - the exact mechanism depends on the source platform and should be scoped per migration.

How long does a migration take?

It depends on event volume, taxonomy complexity, and how many downstream dashboards/alerts depend on the old platform - we scope a timeline per engagement rather than quoting a generic number.

Do you migrate feature flags and session replay too, or just analytics events?

All three, when relevant - flag-by-flag mapping if migrating from another flagging tool, and replay configuration (sampling, masking) is set up fresh on PostHog rather than migrated, since replay data itself generally is not portable between platforms.

Scoping a migration onto PostHog?

Tell us the source platform and rough event volume, and we'll come back with a mapping approach and a realistic timeline.

Scope My Migration