Whenever a tool is free, it's worth asking how. Here's how.
Four revenue streams
- Paid tier for teams that need priority queueing, > 90-day retention, and uptime SLAs.
- Enterprise API for platforms embedding Inbox Check (ESPs, CRMs, MCP/A2A orchestrators).
- Deliverability research partnerships that fund the seed network.
- Paid add-ons: dedicated seeds, private-tenant Microsoft 365 diagnostics, custom provider additions.
Why the core is free
- Placement measurement is a public-interest problem. Charging for baseline measurement distorts the market (warmup vendors selling circular scores).
- Free usage grows the seed network's signal quality. The more tests we run, the better our anomaly detection and per-provider weighting.
- Trust is the asset. Teams who use us free during their deliverability audit become the enterprise customers later.
What it costs us
Most of the cost is the seed network and the infrastructure around it. Seed maintenance (anti-lockout, rotation, rotating providers) is the biggest ongoing line. API+worker infra is modest by comparison. The math works because free-tier users share the seed fleet with paid-tier users, and paid tiers cover the fixed costs.
Commitments
- Core placement test stays free.
- No rugpulls. If we ever moved a feature to paid, existing use keeps working at current limits.
- No hidden ad-insertion in results. No customer-data resale.
- Rate limits sized for real work, not trial-bait.
Start free
Try it. If you ever need more, the paid tier is there; if you don't, the free tier is permanent.
FAQ
Are you VC-funded with a plan to monetise later?
No. We're self-funded with paid-tier and enterprise revenue already covering operations. The free tier is sustainable, not a runway-burn.
What if the seed network gets too expensive?
We scale paid tier capacity and maintain free-tier at a supportable limit. Free-tier limits today are sized so that even at 10x growth, the network can absorb it.
Why not show ads?
No. A placement-testing tool that shows ads has every incentive to keep you worried about deliverability instead of fixing it.
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