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About
What is sending.ac
sending.ac provisions Azure-hosted mailboxes and automates the full DNS authentication stack — SPF, DKIM, and DMARC — so teams can run high-volume cold email without manually configuring infrastructure. It's built for SDRs, BDRs, agencies, and RevOps teams sending 30,000 or more emails per month who need to manage hundreds of mailboxes without inbox placement degrading at scale. The standout capability is per-domain isolation: each domain operates independently, so a deliverability issue on one doesn't bleed into the rest of your sending pool. The minimum order is 450 mailboxes, which means this isn't a fit for solo senders or teams running light outreach — the entry point assumes you're already operating at volume.
Capabilities
Key features
Deliverability infrastructure
warmup, spam tests, and sender reputation
Our verdict
Vanderbuild take
sending.ac is pure infrastructure — it handles the mailbox provisioning and DNS authentication layer that agencies, RevOps teams, and high-volume SDR orgs typically spend hours configuring manually. On the agentic readiness front, there's no API and no MCP server; this is UI-only, which means you can't drive it programmatically from an agent or orchestration layer without scraping — a real ceiling if you're building automated outbound workflows. At $0.44 per mailbox it's near-free to test relative to what broken deliverability costs, but the 450-mailbox minimum (~$198 entry) means it's sized for teams already running at volume, not someone spinning up their first sequence. The honest gap is integrations: none are listed, so you're managing this as a standalone infrastructure layer and stitching it to your sequencer yourself.
Mateusz Sekta
Founder, vanderbuild
Learn more
Our Resources
GUIDEGTMWhat is GTM Engineering?
What is GTM Engineering? The 2026 guide to the role, tools and salary - plus the top 10 GTM Engineers in North America & Europe.
GUIDEHOW-TOHow to implement outbound in SaaS: costs, tools, and benchmarks [2026]
A complete guide to implementing outbound in SaaS costs from $197, proven tools, benchmarks and legal considerations.
The wedge
Agentic stack profile
APINot publicNo public programmatic access.
API
No public API. Not usable from an agent without scraping.
Agentic readinessNoneNot usable from an agent without scraping.
Agentic readiness
No public API. UI-only. Not usable from an agent without scraping, which we don't recommend.
Stack roleDeliverabilityWhere this tool slots into an agentic pipeline.
Stack role
Plays the role of Deliverability in an agentic pipeline. Use it to keep email sending reputation healthy — warmup, spam tests.
Compare
sending.ac alternatives
Tools that solve a similar problem — compared at a glance.
sending.ac(this tool)
- Pricing
- Seat-based
- Budget
- $
- Best for
- SDR / BDR, Agency
- Readiness
- None
- API
- No
Mailforge
- Pricing
- Usage-based
- Budget
- $
- Best for
- Founder, GTM Engineer
- Readiness
- Capable
- MCP
- No
- API
- REST
Infraforge
- Pricing
- Usage-based
- Budget
- $
- Best for
- SDR / BDR, Agency
- Readiness
- Limited
- API
- REST
Answers
Frequently asked questions
Does sending.ac have a public API?
No — there's no publicly documented API as of today. sending.ac is operated through its UI.
How much does sending.ac cost?
sending.ac: pricing is seat-based, expect entry tier ($) spend. Full pricing page: https://sending.ac/.
Who is sending.ac best for?
sending.ac is built for SDR / BDR, Agency, RevOps. Fits Solo, SMB (1-50)-sized teams.