How to track lead-to-MQL conversion rate by source and report weekly to Slack

Why track conversion by source?

Marketing teams spend $10,000-50,000/month across channels without knowing which ones actually produce qualified pipeline. Your paid ads might generate 500 leads but only 10 MQLs (2% conversion), while organic search produces 50 leads and 15 MQLs (30% conversion). Without source-level conversion tracking, you're optimizing spend based on volume instead of quality.

The typical workflow — exporting from HubSpot, pivoting in a spreadsheet, pasting into Slack — takes 30-45 minutes and usually happens monthly at best. By then, an underperforming channel has burned through weeks of budget. A weekly automated report surfaces these gaps within days, not months.

How it works

Every approach in this guide follows the same pattern:

1. Trigger on a weekly schedule (usually Monday morning)
2. Query HubSpot for contacts created in the last 7 days, pulling hs_analytics_source and lifecyclestage properties
3. Run a second query filtered to contacts where lifecyclestage = marketingqualifiedlead to isolate MQLs
4. Calculate conversion rates per source by comparing lead counts to MQL counts
5. Post a formatted report to Slack with per-source breakdown and overall conversion rate

What you'll need

Which approach should I use?

• Code + Cron if you want zero ongoing cost and full control over the query logic. Best for teams with a developer who can maintain the script. Runs on GitHub Actions for free.
• n8n if you want a visual workflow you can modify without code. Free self-hosted or $24/mo cloud. Good balance of flexibility and maintainability.
• Make if your team already uses Make for other automations. Requires Core plan ($29/mo) for the Code module needed to calculate percentages. Credit-efficient at ~20 credits/month.
• Claude Code if you want conversational flexibility — ask for different time windows, specific source breakdowns, or ad-hoc comparisons without changing any configuration. Best when you need on-demand reports during meetings or strategy sessions.

Select an approach below to see the full step-by-step guide.