Meta Conversions API for embedded forms
When Meta Conversions API (CAPI) delivery is enabled, Siv sends a server-side
Lead event for each accepted Siv web-form submission. Pair it with your
website's browser Pixel event. Meta can then deduplicate the browser and server
events.
Configure server-side delivery
- In Siv, open Settings > Facebook for the property.
- Under Meta Conversions API, enter the Dataset (Pixel) ID that your website's browser Pixel uses. Enter a dedicated CAPI access token.
- Leave Send Lead events for Siv web-form submissions selected.
- To test the connection, enter a current Meta test event code and select Save and validate. Siv uses the code for that request only and does not save it.
This integration sends conversions for accepted Siv web-form submissions only. It does not send CAPI conversions for Facebook Lead Ads imported into Siv.
Deduplicate the browser event
Use the callback's exact eventId as Meta Pixel's eventID:
The browser event and Siv's server event must share all three values:
- Event name:
Lead - Event ID: the callback's exact
eventId - Dataset (Pixel) ID: the same dataset configured in Siv and on the website
Meta cannot deduplicate events sent to different datasets. Siv does not load or call the browser Pixel.
Consent and secrets
Run browser advertising calls only after your consent platform says they are allowed. Store the CAPI token only in Siv settings; never place it in the embed snippet or submission callback.
Troubleshooting duplicate leads
Compare the browser and server events in Meta Events Manager. Confirm both say
Lead, carry the same event ID, and target the same Dataset (Pixel) ID.
If server delivery fails, check its latest status under Settings > Facebook > Meta Conversions API, then validate the saved token with a fresh test event code.