How to Upload Offline Conversions to Facebook (Meta) Ads

Uploading offline conversions to Meta (Facebook/Instagram) requires the Conversions API (CAPI) — Meta’s server-side event tracking endpoint. Unlike Google Ads, which accepts CSV files, Meta requires all offline events to be sent via API.

This guide from The Upload Offline Conversions App (TUOCA) walks through every step, from setup to your first successful event submission.

Prerequisites

• ✅ Meta Business account
• ✅ Facebook/Instagram ad campaigns running
• ✅ Pixel created (required for CAPI access)
• ✅ Access token generated
• ✅ Conversion data (leads with email/phone and conversion details)

Step 1: Create a Pixel (If You Don’t Have One)

1. Go to Meta Events Manager (business.facebook.com/events_manager)
2. Click Connect Data Sources → Web
3. Name your pixel
4. Click Create Pixel
5. Note the Pixel ID (you’ll need this for API calls)

Step 2: Generate an Access Token

1. In Events Manager, select your pixel
2. Click Settings
3. Scroll to Conversions API
4. Click Generate Access Token
5. Copy and securely store the token

Important: This token doesn’t expire automatically, but it’s tied to your user account. If your account permissions change, you may need to regenerate it.

Step 3: Prepare Your Data

Required Fields

Field	API Name	Format	Required
Event name	event_name	String (e.g., “Purchase”)	✅ Yes
Event time	event_time	Unix timestamp	✅ Yes
Action source	action_source	system_generated (for offline)	✅ Yes
Hashed email	user_data.em	SHA-256 of lowercase, trimmed email	✅ At least one
Hashed phone	user_data.ph	SHA-256 of E.164 phone	Recommended

Recommended Fields

Field	API Name	Format	Purpose
fbc	user_data.fbc	fb.1.{timestamp}.{fbclid}	Click-level matching
Event ID	event_id	Unique string	Deduplication
Value	custom_data.value	Number	Revenue tracking
Currency	custom_data.currency	ISO 4217	Currency code

Step 4: Normalize and Hash PII

Critical: PII must be normalized THEN hashed with SHA-256. The order matters.

Email

Raw:      "  John.Doe@Gmail.COM  "
Step 1:   "john.doe@gmail.com"       (lowercase, trim)
Step 2:   SHA-256 hash → "e8b6c3..."  (hash)

Phone

Raw:      "(555) 123-4567"
Step 1:   "+15551234567"              (E.164 format)
Step 2:   SHA-256 hash → "d4f5c3..."  (hash)

Use the SHA-256 Hasher and E.164 Formatter tools to verify.

Step 5: Format the API Request

Endpoint

POST https://graph.facebook.com/v26.0/{PIXEL_ID}/events

Request Body

{
  "data": [{
    "event_name": "Purchase",
    "event_time": 1714502400,
    "event_id": "job-2026-04-001",
    "action_source": "system_generated",
    "user_data": {
      "em": ["e8b6c3a4f2d1..."],
      "ph": ["d4f5c3b1e72a..."],
      "fbc": "fb.1.1714000000.IwAR3x7..."
    },
    "custom_data": {
      "value": 4500.00,
      "currency": "USD"
    }
  }],
  "access_token": "YOUR_ACCESS_TOKEN"
}

Key Notes

• em and ph are arrays — you can send multiple emails/phones per event
• event_time is a Unix timestamp (seconds, not milliseconds)
• action_source must be system_generated for offline CRM events
• fbc is the processed FBCLID (format: fb.1.{timestamp}.{fbclid})

Step 6: Send the Event

Using cURL (Testing)

curl -X POST \
  "https://graph.facebook.com/v26.0/YOUR_PIXEL_ID/events" \
  -H "Content-Type: application/json" \
  -d '{
    "data": [{
      "event_name": "Purchase",
      "event_time": 1714502400,
      "event_id": "test-001",
      "action_source": "system_generated",
      "user_data": {
        "em": ["YOUR_HASHED_EMAIL"]
      },
      "custom_data": {
        "value": 100.00,
        "currency": "USD"
      }
    }],
    "access_token": "YOUR_TOKEN"
  }'

Successful Response

{
  "events_received": 1,
  "messages": [],
  "fbtrace_id": "ABC123..."
}

Step 7: Verify in Events Manager

1. Go to Events Manager → your pixel
2. Click Test Events tab
3. Check that your test event appears
4. Click the Overview tab to see event counts
5. Check Event Match Quality — aim for 6+ (out of 10)

The 7-Day Window Challenge

Meta’s event window is only 7 days. For service businesses with longer sales cycles, you need a strategy:

Strategy: Multi-Stage Events

Day 0:  Ad click (FBCLID captured)
Day 1:  Phone call → Send "Contact" event ✅ (within 7 days)
Day 3:  Estimate scheduled → Send "Lead" event ✅ (within 7 days)
Day 14: Job booked → Send "Purchase" ❌ (outside 7 days for FBCLID)
        BUT: Send with hashed email/phone → PII matching still works

Upload the high-funnel event (“Contact”) within 7 days to establish the click-level match. Then send the final revenue event with hashed PII for people-based matching.

Common Errors

Error	Cause	Fix
Invalid hash format	PII not properly SHA-256 hashed	Use 64-character hex lowercase
Missing user_data	No matching identifiers	Include at least em or ph
Invalid event_time	Timestamp too old or future	Must be within 7 days, not in the future
Duplicate event	Same event_id sent twice	Expected — Meta silently deduplicates
Permission denied	Token expired or lacks scope	Regenerate access token

How TUOCA Automates Meta Uploads

TUOCA handles the entire CAPI pipeline:

1. Data extraction — Pulls from CallRail, CRM, or webhooks
2. PII normalization — Lowercases email, formats phone to E.164
3. SHA-256 hashing — Hashes all PII per Meta’s requirements
4. fbc construction — Converts raw FBCLIDs to fbc format
5. Event formation — Builds the CAPI JSON payload
6. Batch upload — Sends events to the Conversions API
7. Deduplication — Generates consistent event_ids
8. Error handling — Logs and categorizes API errors
9. EMQ monitoring — Tracks Event Match Quality scores

Next Steps

1. ✅ Create pixel and generate access token
2. ✅ Send a test event via cURL
3. ✅ Verify in Events Manager → Test Events
4. ✅ Set up TUOCA for automated CAPI uploads
5. ✅ Monitor Event Match Quality — aim for 6+