Cold Email ROI API
Forecast cold email campaign outcomes programmatically. The Cold Email ROI API turns campaign assumptions into estimates for replies, meetings, clients, revenue, ROI, cost per meeting, performance grade, risk flags, and recommendations. Built for agencies, CRM tools, AI sales agents, outbound dashboards, and RevOps teams.
What the Cold Email ROI API Does
Send a POST request with campaign assumptions:
- Required: emails_sent, reply_rate, positive_reply_rate, meeting_booking_rate, close_rate
- Optional: average_deal_value, campaign_cost
Get back a complete forecast: estimated replies, meetings, clients, revenue, ROI multiple, cost per reply, cost per meeting, cost per client, performance grade, risk flags, and recommendations — all in structured JSON.
The API does not send emails. It forecasts outcomes based on your assumptions. Always test assumptions against real campaign data.
Why Use a Cold Email ROI API?
Most cold outreach campaigns launch without a clear forecast of what they will produce. Without a forecast, teams cannot set realistic expectations, compare scenarios, or budget effectively. The Cold Email ROI API solves this by providing a deterministic, repeatable forecast from the same inputs teams already use to plan campaigns.
Agencies use it to model campaign scenarios before pitching clients. CRM tools embed it to show projected outcomes inside deal views. AI agents call it to evaluate outreach strategies autonomously. RevOps teams use it to compare multiple campaign plans side by side.
API Endpoint
Content-Type: application/json
x-api-key: YOUR_API_KEY
Request Inputs
| Field | Type | Required | Description |
|---|---|---|---|
| emails_sent | integer | Yes | Total campaign email volume. Min 1, max 1,000,000. |
| reply_rate | number | Yes | Expected reply rate as a percentage (e.g. 5 means 5%). 0-100. |
| positive_reply_rate | number | Yes | Percentage of replies that are positive or interested. 0-100. |
| meeting_booking_rate | number | Yes | Percentage of positive replies that book a meeting. 0-100. |
| close_rate | number | Yes | Percentage of meetings that become customers. 0-100. |
| average_deal_value | number | No | Average revenue per customer. Defaults to 0. |
| campaign_cost | number | No | Total campaign cost. Defaults to 0. |
Response Outputs
| Field | Description |
|---|---|
| estimated_replies | Total replies from sent volume and reply rate. |
| estimated_positive_replies | Interested or qualified replies. |
| estimated_meetings | Projected meetings booked. |
| estimated_clients | Expected customers from meeting close rate. |
| estimated_revenue | Forecasted revenue from clients and deal value. |
| roi_multiple | Revenue divided by campaign cost (null if cost is 0). |
| cost_per_reply | Campaign cost divided by replies. |
| cost_per_meeting | Campaign cost divided by meetings. |
| cost_per_client | Campaign cost divided by clients. |
| performance_grade | strong, healthy, break_even_or_unclear, or weak. |
| risk_flags | Deterministic warnings about campaign assumptions. |
| recommendations | Actionable next steps based on forecast. |
| calculation_notes | Interpretation notes for the forecast. |
Example Request
-H "Content-Type: application/json" \
-H "x-api-key: YOUR_API_KEY" \
-d '{
"emails_sent": 5000,
"reply_rate": 5,
"positive_reply_rate": 30,
"meeting_booking_rate": 20,
"close_rate": 25,
"average_deal_value": 2500,
"campaign_cost": 600
}'
Example Response
"estimated_replies": 250,
"estimated_positive_replies": 75,
"estimated_meetings": 15,
"estimated_clients": 3.75,
"estimated_revenue": 9375,
"roi_multiple": 15.6,
"cost_per_reply": 2.4,
"cost_per_meeting": 40,
"cost_per_client": 160,
"performance_grade": "strong",
"risk_flags": [],
"recommendations": [...],
"calculation_notes": [...]
}
Use Cases
API Pricing
Pay-as-you-go credit packs. 1 credit = 1 forecast request. Buy credits when you need them. No monthly subscription.
| Plan | Price | Credits |
|---|---|---|
| Free | $0 USD | 100 |
| Starter Pack | $29 USD | 1,000 |
| Growth Pack | $79 USD | 5,000 |
| Scale Pack | $199 USD | 20,000 |
Credit packs are one-time purchases. View full pricing details.
Authentication
API keys are sent in the x-api-key header:
API access is reviewed within 1 business day. Request API access at coldmailcalculator.com/api/get-key/ or purchase a credit pack to receive a key. For local testing, the key demo_test_key works in non-production environments.
Error Responses
The API returns standard HTTP status codes and JSON error bodies:
| Status | Error Type | Meaning |
|---|---|---|
| 400 | invalid_request | Missing, invalid, or out-of-range fields. |
| 401 | unauthorized | Missing or invalid API key. |
| 405 | method_not_allowed | Only POST is accepted. |
| 500 | server_config_error | API access is not configured. |
Limitations
Forecasts are estimates for planning and product workflows. They should not be treated as guaranteed replies, meetings, clients, revenue, deliverability, or inbox placement. The Cold Email ROI API does not send email, manage inboxes, scrape leads, write messages, or replace compliance review.
Rate limits apply per API key. Contact support@coldmailcalculator.com to request custom rate limits for high-volume production use.
Start Using the API
Explore the ColdMail API overview page to get started and learn more. Read the full API documentation for detailed request/response schemas. Try code examples in JavaScript, cURL, and Python. Or use the free web calculator now — no API key required.
Build cold email forecasting into your product
The Cold Email ROI API gives your tools the same forecasting engine used by agencies, CRM platforms, and AI agents.
FAQ
What is the Cold Email ROI API?
The Cold Email ROI API is a REST endpoint that forecasts cold email campaign outcomes from simple campaign assumptions. It returns structured JSON with estimated replies, meetings, clients, revenue, ROI, and more.
How does the Cold Email ROI API work?
Send a POST request to /api/v1/forecast with campaign inputs. The API applies a deterministic funnel model and returns structured forecasts.
Is the Cold Email ROI API free?
There is a free tier with 100 credits. Paid credit packs start at $29 for 1,000 credits. Request API access at coldmailcalculator.com/api/get-key/.
Who is the Cold Email ROI API for?
Agencies, CRM platforms, AI sales agents, outbound reporting tools, RevOps teams, and developers needing programmatic campaign forecasting.
Can I use the Cold Email ROI API with AI agents?
Yes. The API returns structured JSON that AI agents, LLM tools, and automation workflows can consume directly.
What inputs does the API need?
Required: emails_sent, reply_rate, positive_reply_rate, meeting_booking_rate, close_rate. Optional: average_deal_value, campaign_cost.
What does the API return?
Estimated replies, positive replies, meetings, clients, revenue, ROI, cost per reply, cost per meeting, cost per client, performance grade, risk flags, and recommendations.
Does the API guarantee campaign results?
No. The API provides estimates based on input assumptions. Actual results depend on targeting, offer, timing, and execution.