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TechnologyGenerated accuracy model review: 2026-05-06

Email Sending Cost Calculator accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • Monthly cost = emails / 1000 * price per thousand + attachment GB * transfer price + dedicated IP fee + validation cost + fixed fee.

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Monthly Emails: 500,000
  • Send Price: 0.8 $/1k
  • Attachment Transfer: 25 GB
  • Transfer Price: 0.08 $/GB
  • Dedicated IP Fees: $25
  • Validation Cost: $0
  • Fixed Monthly Fee: $0

Expected outputs

  • Monthly Email Cost: $427.00
  • Send Cost: $400.00
  • Add-on Cost: $27.00
  • Cost per Email: $0.00

Known limitations

  • This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
  • Use the result as a planning estimate unless the calculator page states a stricter purpose.

Assumptions

  • Prices are user-entered flat rates.
  • Deliverability, bounces, suppression, and compliance tooling are not modeled.
  • Email lists or content are not uploaded.

Unit handling

  • Monthly Emails accepts numeric values.
  • Send Price accepts values in $/1k.
  • Attachment Transfer accepts values in GB.
  • Transfer Price accepts values in $/GB.
  • Dedicated IP Fees accepts values in $.
  • Validation Cost accepts values in $.
  • Fixed Monthly Fee accepts values in $.
  • Monthly Email Cost is displayed as currency.
  • Send Cost is displayed as currency.
  • Add-on Cost is displayed as currency.
  • Cost per Email is displayed as currency.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.
  • Currency outputs are displayed with standard US dollar formatting.
  • Input precision follows configured step values where provided.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current email-sending-cost-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Email Sending Cost Calculator.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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