What Is the Reddit Conversion API?
The Reddit Conversion API (CAPI) lets you send conversion events from Cometly directly to Reddit Ads. This gives Reddit more complete data about how your ads are performing, even when browser-based tracking misses events due to ad blockers, cookie restrictions, or cross-device behavior.
With CAPI enabled, Cometly automatically sends your conversion events to Reddit using the Pixel ID associated with your ad account. You can choose to send all events or only events attributed to Reddit.
Before You Begin
Make sure you have the following in place before configuring CAPI:
A connected Reddit profile. You need to sign in with Reddit through Cometly's Integrations page so Cometly has permission to communicate with your Reddit Ads account.
A Reddit Ad account connected to your Space. The ad account you want to send conversions to must be linked to your current Space.
Your Reddit Pixel ID. Each Reddit Ad account has a Pixel ID. You'll need this during the CAPI configuration step. You can find it in your Reddit Ads Manager.
Step 1: Connect Your Reddit Profile
If you haven't already connected your Reddit profile:
Go to Integrations
Find the Reddit section
Click Sign in with Reddit
Authorize Cometly in the popup window
If your Reddit account is associated with multiple businesses, you'll be asked to select which one to use
Once connected, your Reddit profile will appear on the Integrations page
Step 2: Connect Your Ad Account to Your Space
On the Integrations page, find your connected Reddit profile
You'll see a list of ad accounts associated with that profile
Click Connect & Sync Data next to the ad account you want to use
The account is now linked to your current Space and ready for CAPI configuration
Step 3: Enable and Configure the Reddit Conversion API
Navigate to the Events Manager page and click Conversion API in the top menu
Find the Reddit section
Choose a data sharing mode:
Off. No events are sent to Reddit.
Only send attributed events. Only sends events to Reddit when Cometly attributed the conversion to a Reddit ad. This is the most conservative option and avoids inflating your Reddit conversion counts.
Send all events. Sends every matching event to Reddit, regardless of which ad platform gets the attribution.
Enter your Pixel ID for each connected Reddit Ad account. This tells Cometly where to send the conversion data on Reddit's side.
Select a default account. If you choose "Send all events," you'll need to pick a default Reddit Ad account. This is the account that will receive events that aren't directly attributed to any specific Reddit ad.
Click Save
Custom Rules (Optional)
By default, all events follow the master data sharing mode you selected above. If you want to override the behavior for specific events, you can set up custom rules.
For example, you might set your master mode to "Send all events" but create a custom rule for your "Lead" event to "Only send attributed." This gives you granular control over which events are shared and how.
Custom rules support the same three modes: Off, Only send attributed, and Send all events.
Supported Events
Cometly automatically maps your events to Reddit's supported conversion types:
Cometly Event | Reddit Event Type |
Purchase | PURCHASE |
Lead | LEAD |
Sign Up | SIGN_UP |
Add to Cart | ADD_TO_CART |
Page Visit | PAGE_VISIT |
View Content | VIEW_CONTENT |
Search | SEARCH |
Add to Wishlist | ADD_TO_WISHLIST |
Any custom event | CUSTOM |
Custom events are sent as the CUSTOM type with your event name included. Custom events must be configured in your Space's event settings to be sent through CAPI.
What Data Gets Sent to Reddit
When a matching event fires and CAPI is enabled, Cometly sends the following data to Reddit:
Data | Description |
Event Type | The mapped Reddit event type (see table above) |
Event Timestamp | When the event occurred |
Conversion Value | The monetary value of the event (if available) |
Currency Code | Your Space's currency setting |
Reddit Click ID (rdt_cid) | The click identifier from the original Reddit ad click (if available) |
Hashed Email | SHA-256 hashed, normalized email address (if available) |
Hashed Phone Number | SHA-256 hashed, normalized phone number (if available) |
Hashed External ID | SHA-256 hashed external identifier (if available) |
IP Address | The user's IP address (if available) |
User Agent | The user's browser user agent (if available) |
UUID | A unique user identifier (if available) |
Cometly normalizes and hashes all personal data (email, phone, external ID) using SHA-256 before sending. Raw personal data is never shared with Reddit.
How Attribution Works
When a user clicks a Reddit ad, a click ID (rdt_cid) is captured and stored with the event data. Cometly uses this click ID to determine which Reddit Ad account the conversion should be attributed to.
Attributed events. If a rdt_cid is present, Cometly traces it back to the specific ad, ad group, campaign, and account. The event is sent using that account's Pixel ID.
Unattributed events. If no rdt_cid is present (and you've chosen "Send all events"), Cometly sends the event to your default Reddit Ad account using its Pixel ID.
Turning CAPI Off
To disable the Reddit Conversion API:
Navigate to the Conversion API page
Find the Reddit section
Set the data sharing mode to Off
Click Save
No events will be sent to Reddit while CAPI is off. Your Pixel IDs, default account, and any custom rules are preserved, so you can turn it back on at any time without reconfiguring.
Troubleshooting
If conversions aren't appearing in Reddit Ads, check the following:
Is CAPI turned on? Make sure the data sharing mode is not set to "Off."
Is the Pixel ID entered? Each connected Reddit Ad account needs a valid Pixel ID. Without it, Cometly can't send events to Reddit.
Is the event supported? Standard events are mapped automatically. For custom events, make sure the event is configured in your Space's event settings.
Is the account active? Make sure the Reddit Ad account is still connected and active in your Space.
Are you using "Only send attributed"? If this mode is selected and Cometly didn't attribute the conversion to Reddit, the event won't be sent. Try switching to "Send all events" to test.
Is there a connection issue? If you see a "Connection Issue, Resync Required" message on the Integrations page, your Reddit profile may need to be reconnected. Disconnect and sign in again to refresh the connection.
FAQ
What's the difference between "Send all events" and "Only send attributed events"?
"Send all events" sends every matching conversion to Reddit, regardless of which platform Cometly attributed it to. "Only send attributed events" only sends conversions that Cometly determined came from a Reddit ad. Use "Only send attributed" if you want to avoid sending unrelated conversions to Reddit.
Do I need a Reddit Pixel installed on my website if I'm using CAPI?
CAPI works independently of the browser-based Reddit Pixel. However, using both together gives Reddit the most complete picture of your conversion data.
Can I use different settings for different events?
Yes. Use custom rules to override the master data sharing mode for individual events. For example, you can send all Purchase events but only send attributed Lead events.
Where do I find my Reddit Pixel ID?
You can find your Pixel ID in the Reddit Ads Manager under your account's conversion tracking settings.
Is personal data shared with Reddit?
Email addresses, phone numbers, and external IDs are normalized and hashed (SHA-256) before being sent. Cometly never sends raw personal data to Reddit. IP addresses and user agents are sent unhashed, as Reddit requires them in their original format for matching.
How quickly do conversions appear in Reddit Ads?
Conversions are sent in real time as events come in. However, Reddit may take some time to process and display them in reporting.