SPF & DMARC Checker · Office #43,689

What it is

Calls itself “Checker”.

• Calls itself: Checker

“Checker”

What it costs

Monthly subscription. A free tier, free forever. Sales on request.

• Monthly: yes
• Free plan: free forever
• Contact sales: yes

“Ongoing development, support, automation or IT for a predictable monthly fee. Monthly rolling plan”

“Free · No sign-up · Nothing stored”

Who it sells to

Sells to businesses. Built for small businesses.

• Sells to: businesses
• Company size: small businesses

“Most small businesses aren't protected”

How it runs

A web app for Linux, Windows and macOS. Runs locally and works offline.

• Kind: web
• Runs on: Linux · Windows · macOS
• Runs where: on the device, offline

“The checker runs in your browser and needs JavaScript.”

“On macOS or Linux, run dig +short TXT _dmarc.yourbusiness.com”

What it works with

Integrates with Cloudflare and Google. Names Google Workspace, HubSpot and 4 more on its pages.

• Integrates with: Cloudflare · Google
• Names: Google Workspace · HubSpot · Mailchimp · +3

“The lookups run in your browser through Cloudflare's public DNS (Google's as a backup)”

“Knows 30+ senders: Google Workspace, Microsoft 365, Zoho, Mailchimp, HubSpot and more”

What it offers as proof

Live, no waitlist. Claims “1,728”. Try it without signing up. Publishes docs, a blog and a careers page.

• Number claimed: 1,728
• Trial asks for: nothing

“Runs in your browser: no sign-up, nothing stored”

“ZNova study of 1,728 local business domains, October 2026.”