Endpoint

POST https://www.coldmailcalculator.com/api/v1/coldmail/roi

Returns a campaign ROI forecast. All request fields are required. Responses are in JSON format.

Authentication

All API requests require an API key passed via the x-api-key header.

x-api-key: YOUR_API_KEY

To get an API key, request developer preview access.

Request Fields

Field Type Description
emails_sent integer Total number of emails sent in the campaign required
delivery_rate float (0–1) Fraction of emails that reached the inbox required
reply_rate float (0–1) Fraction of delivered emails that got any reply required
positive_reply_rate float (0–1) Fraction of replies that are positive / interested required
booking_rate float (0–1) Fraction of positive replies that book a call required
close_rate float (0–1) Fraction of booked calls that close into a customer required
average_deal_value float Average revenue per closed deal in USD required
monthly_tool_cost float Monthly cost of your tools / software in USD required
sending_infrastructure_cost float Monthly cost of email infrastructure in USD required

Response Fields

Field Type Description
positive_replies integer Estimated number of positive / interested replies
booked_calls integer Estimated number of booked calls
estimated_revenue float Estimated total revenue in USD
estimated_profit float Estimated profit after costs in USD
campaign_score float (0–100) Overall campaign health score
risk_level string Risk assessment: low, medium, or high

Example Response

{ "positive_replies": 13, "booked_calls": 5, "estimated_revenue": 3000, "estimated_profit": 2851, "campaign_score": 68, "risk_level": "medium" }

Error Codes

Status Code Meaning
200Success — forecast returned
400Bad request — missing or invalid fields
401Unauthorized — missing or invalid API key
429Rate limit exceeded — upgrade your plan for more calls
500Internal server error — try again later

Error responses include a JSON body with a message field describing the issue.

Rate Limits

Pack Price Credits
Developer Preview$0 USD100 forecast credits for testing
Starter Pack$29 USD1,000 credits
Growth Pack$79 USD5,000 credits
Scale Pack$199 USD20,000 credits
EnterpriseCustomCustom
Rate limit headers — Each response includes X-RateLimit-Limit, X-RateLimit-Remaining, and X-RateLimit-Reset headers so you can track usage programmatically.

Developer preview includes 100 forecast credits for testing. No credit card required. Buy credit packs when you need more. See full pricing for details.

Next Steps

Get started quickly — Browse code examples in cURL, JavaScript, and Python, or read the full API documentation for integration guides.

Ready to start forecasting?

Request API access and start calculating campaign ROI today.

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