emailhealth

A terminal tool that checks a domain's email deliverability health. Point it at an email address and it looks up the domain's DNS records — MX, SPF, DKIM, DMARC, and more — and renders an interactive report in your terminal.

Features

emailhealth runs the following checks against the domain of the email address you give it:

• NS Records — confirms the domain resolves and has nameservers
• IP Address (A record) — resolves the domain's A record
• MX Records — fetches and sorts mail exchanger records, flags null MX records
• TXT Records — fetches all TXT records for the domain
• SPF Records — checks _spf.<domain> and falls back to scanning TXT records for a v=spf1 entry
• DMARC Records — checks _dmarc.<domain>
• DKIM Records — checks _domainkey.<domain> plus a set of common selectors (default, google, k1, s1, s2, selector1, selector2), and flags revoked/empty keys (p=) or RSA keys under 1024 bits

Each check is reported as healthy, unhealthy, or unknown, and an overall health score (percentage of healthy checks) is shown in the header. Results are displayed as an interactive, collapsible accordion in the terminal, with a button to copy any individual report to your clipboard.

Requirements

• Node.js 18+
• Yarn

Installation

Global install from NPM

npm install -g emailhealth

From source

git clone https://github.com/charlesinwald/emailhealth.git
cd emailhealth
yarn install
yarn build

Usage

From a local clone, run:

yarn start [email protected]

This compiles the TypeScript sources and runs the CLI against the domain of the given email address (example.com in this case — the local part of the address isn't used for lookups).

Inside the report view:

| Key | Action | | -------------- | ---------------- | | Mouse | Full interaction | | Up Arrow | Scroll up | | Down Arrow | Scroll down | | Enter | Open a section | | q | Quit |

Development

yarn build   # compile TypeScript to dist/
yarn test    # compile and run the test suite (node --test)

Source lives in src/:

• src/index.ts — CLI entry point and terminal UI (built with @rezi-ui)
• src/checkEmailHealth.ts — DNS lookups and health check logic
• src/utils.ts — CLI argument parsing, formatting, and helper functions
• src/types.ts — shared types

Tech stack

• TypeScript
• Node.js dns for DNS resolution
• Commander for CLI argument parsing
• @rezi-ui/core / @rezi-ui/node for the terminal UI

License

ISC