How to use the Facebook Lead Testing Tool

The Meta Lead Ads Testing Tool is a free developer tool at developers.facebook.com/tools/lead-ads-testing that lets you send fake leads through your live Facebook and Instagram lead forms to verify that webhooks, CRM connections, and email notifications are firing correctly — without spending ad budget. You need admin or advertiser access on the connected Page to use it.

This guide walks through how to use the tool, what to do when it stops working, and the common error codes you’ll see in Track Status — whether you’re using LeadSync, Zapier, Make, or a direct CRM integration.

Key takeaways

• The tool lives at developers.facebook.com/tools/lead-ads-testing and is free; only one test lead can be submitted per form at a time.
• You need Page admin or advertiser access. Lead Access alone is not enough for the Preview Form button.
• Track Status shows real-time webhook delivery — use it to debug CRM integrations and identify the error code.
• If the tool shows “Something went wrong” or the Preview button is missing, see Tool Not Working? below for current workarounds.
• Test leads trigger the same webhook as live leads, so your CRM treats them identically.

Step-by-Step Guide to Using the Facebook Lead Ad Testing Tool

Basic Steps

1. Navigate to the Testing Tool: Go to Facebook’s Lead Ads Testing Tool.
2. Select Your Page: Choose the relevant Facebook Page and Form from the dropdown menus. Facebook will automatically show you if you have permissions to access leads, if you have lead access manager enables and if you are a Page Admin. Under this section you’ll also be able to see which Applications have access to your leads. If you’re using LeadSync, make sure this is showing with a tick. If you’re seeing an orange warning icon, click on the arrow on the right for more details about the issue.

3. Select Your Form: From the dropdown, select the form that you want to test, making sure that this is the same form you have setup in the integration tool you’re using AND the same form you’re using in your Meta Ads.

4. Preview your Form: the best way to test your form is to use the Preview Form option. This lets you fill in the form details with real data. Some CRM’s will reject the generic data that’s submitted with

5. Create a Lead: If you don’t want to submit your own details, via the preview form option, just click the ‘Create lead’ button to proceed and test lead form data will be sent. Remember, only ‘one lead’ can be submitted per form at a time, so it’s crucial to test each form individually.

6. Test Lead Sent: You should now see “Your test lead has been sent” message.

7. Track Status: After 20 few seconds or so, click on “Track Status” to see if the lead has been successfully created. If you’re using LeadSync, you should see the following success message.

The LeadSync App ID will either be 1711149865783520 or 559339176323491

8. Check your Email, CRM or APP: Make sure you’ve received the test data to the connection you’ve setup in LeadSync or Zapier.

Advanced Features

• Preview Form: Before submitting, you can preview the form to customize the data being sent.
• Error Handling: If you encounter a 103 error, it means CRM access has been revoked. You’ll need to reset the Facebook Leads Access CRM permissions.

Tool Not Working? Common Errors and Fixes

Meta’s testing tool has been intermittently broken throughout 2026 — blank screens, vanished Preview buttons, and “Something went wrong” errors. Here’s what users on r/PPC, r/FacebookAds, and r/zapier have actually confirmed works in the past few months. If none of the fixes below resolve your issue, Workaround: Use Ads Manager’s Test Form feature at the bottom is the reliable fallback.

“Something went wrong. Please try again later.”

This error became widespread in 2026 and appears intermittently — multiple users report it resolving on its own without any changes on their end, which strongly suggests it’s a Meta backend issue rather than a configuration problem.

Things to try first, in order:

1. Clear cookies for developers.facebook.com and facebook.com, then sign back in. This is the most commonly reported fix in r/PPC and r/zapier threads.
2. Try Chrome incognito or a different browser to rule out a corrupted session.
3. Verify your Business Manager account if the tool prompts you — some users report being asked to re-verify when the error first appears.

If none of the above works, treat it as a Meta-side outage and use the Workaround below.

Preview Form button missing

In 2026 Meta confirmed via support escalation that the Preview Form feature has been temporarily disabled “as we work on enhancements” — with no ETA for restoration. This is happening on Meta’s side regardless of your Page configuration, permissions, or form status, so the usual checks (Page admin role, form not archived, creative attached) won’t bring it back.

Meta’s suggested replacement is the Create Lead button, but that only sends generic dummy data — you can’t fill out the form with real values that way. For real-data testing, use the Workaround below.

Track Status shows “failed” with code 100, 103, or 190

These are token or permission errors, not tool bugs:

• Code 100, subcode 33 — You’re using a Page token to test an ad-level integration. Switch to a Business System User token.
• Code 103 — CRM access has been revoked. Reset Lead Access permissions for the integration app under Page Settings > Lead Access.
• Code 190 — Your CRM’s connection token has expired. Reconnect the integration in your CRM’s Facebook settings.

LeadSync customers can reconnect their Facebook account from their account connections page, or contact LeadSync support to have a token verified directly.

Test lead stuck on “Pending” status

This is a known issue in 2026 — some test submissions never resolve to “success” or “failed”. The reliable fix:

1. In the Lead Ads Testing Tool, select the same Page and Form.
2. Click Delete Lead to clear the pending submission.
3. Submit a fresh test via the Workaround below.

Form dropdown is empty after selecting a Page

If no forms appear after picking your Page, the usual causes are:

1. The Page genuinely has no published lead forms yet (check Forms Library in Meta Business Suite).
2. Your account doesn’t have Lead Access for the Page (Business Settings > Integrations > Lead Access).
3. The API call returned stale data — switch to a different Page in the dropdown and back to force a refresh.

Workaround: Use Ads Manager’s Test Form feature

When the testing tool is broken — Preview button missing, page won’t load, or tests stuck on Pending — this sequence is the verified workaround that has been reported working repeatedly in 2026:

1. Open Ads Manager and select the Page connected to your form.
2. Navigate to All Tools > Instant Forms.
3. Find your form in the list and click Test Form.
4. Fill out the form with real test data. The submission triggers webhooks identically to a live lead — your CRM, email integration, or Zap will receive it.
5. Return to the Lead Ads Testing Tool, select the same Page and Form, and click Delete Lead to clear the test submission so the form remains testable again.

Some users have warned that submitting via a live ad’s dark-post preview link (an older workaround) is risky because it counts as an actual lead and distorts campaign conversion data. The Instant Forms > Test Form path above avoids that.

Troubleshooting Common Issues

Debugging Real-Time Update Integration

If you’re facing issues with your integration with Facebook’s Webhooks, here’s how to debug:

1. Use the tool to create a test lead.
2. Check the status of the lead. If it’s pending, wait a few seconds and check again.
3. Once the lead is pushed to your endpoint, the status should change to “success” or “failed,” providing insights into what might be going wrong.

API Interactions

For those who prefer a more technical approach, you can create a test lead by making a POST request to /{FORM_ID}/test_leads. Make sure you meet the following requirements:

• No existing test leads for the specified Lead Ad form.
• A page role of Advertiser or above on the page under which the form was created.

Other Common Reasons Why You Might Not be Receiving Leads

1. The lead form you’re using in your lead ad hasn’t been set up in your LeadSync Account. Please check to make sure you’ve connected the correct lead form in your LeadSync account.
2. You lead notification is sitting in your spam folder.
3. The email address you’re sending leads to is incorrect.

Please be sure to check these before contacting LeadSync support.

Next Steps

Once you’ve confirmed your test leads are coming through, here are some useful resources to help you get the most out of your lead ad campaigns:

• Improve your targeting: Use our complete Facebook & Meta Ads targeting guide to find the right audience for your campaigns.
• Stay compliant: Generate a free privacy policy for your lead ads — it’s required by Meta for all lead forms.
• Target high-value leads: Learn 12 ways to target high net worth individuals on Facebook & Instagram.
• Get instant lead notifications: Set up Facebook lead email notifications so you receive every lead in your inbox the moment it comes in.
• Connect to your CRM: See our complete integration guide for connecting your lead ads to Mailchimp, HubSpot, ActiveCampaign, and 20+ other tools.