Email deliverability software for B2B teams.
The API details below are not linked to a current official developer page. Confirm them with the vendor before implementation.
| Plan | Price | Included | Notable |
|---|---|---|---|
| Folderly (core product) — Yearly | $96 per mailbox/month (billed yearly, marketed as 'Save 20%') | — | Boost sender reputation with everyday maintenance and best practices |
| Inbox Insights — Free | $0/month | 2 tests per month | |
| Inbox Insights — Monthly | $79/month | 100 tests/month | |
| Inbox Insights — Yearly | $799/year (marketed as 'Save 15%') | 100 tests/month | |
| Pulse | $0/month (marketed as 'It's free!') | — | Monitor spam placement and receive real-time alerts via Email, Slack, SMS, and other channels |
Checked 2026-08-07 against their pricing page. Vendors change pricing without notice.
It publishes 32+ customer case studies claiming a 96.7% average deliverability rate.
B2B outbound teams scaling cold or warm email programs who need continuous deliverability management rather than a one-off warm-up tool, spanning small businesses (per its own case studies, e.g. Adhesive Media at up to 50 employees) through enterprise (e.g. Willow Tree, described as over 250 employees).
Folderly explicitly positions itself as not a warm-up tool, so teams looking specifically for a low-cost, self-serve warm-up product rather than an ongoing managed deliverability service are working against its stated model. The core Folderly product is priced per mailbox per month ($96/mailbox/month on the yearly plan per the products page), which scales with mailbox count and can get expensive for teams running many sending mailboxes; Inbox Insights' free tier is limited to 2 tests per month, well below what an active outbound program would need.
No curated rival set covers this tool yet, so these are simply other tools in the same architectural layer and product form. Treat it as a starting point, not a shortlist.
No. Folderly's own llms.txt explicitly states it is 'not an email warm-up tool,' framing warm-up as one signal among many that 'crumbles as outbound scales,' and instead offers ongoing management of the full deliverability infrastructure.
$96 per mailbox per month on the yearly billing plan (marketed as a 20% savings vs. monthly), per the products/pricing page.
Yes - Inbox Insights has a free tier (2 tests/month), Pulse is marketed as free, and there are standalone free tools: an SPF generator and a spam-words checker.
The vendor names Amazon AWS, Sendpulse, Elastic Email, Google Workspace, SendGrid, and Microsoft Outlook among its integrations, and states it connects via API and SMTP with major ESPs and supports custom providers.
The vendor states each customer is paired with a dedicated deliverability specialist accountable for the outcome, not just tool configuration - a hybrid of software and managed service.
The vendor states it is SOC 2 and ISO 27001 certified.
This is an absence of what we could find, not confirmation Folderly has no API.
This page tells you whether Folderly fits. Cheetah builds and runs the system it goes into — enrichment, sequencing, CRM and the joins between them.
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