The 12 Best Email Deliverability Tools for SaaS Teams
Deliverability is not one problem, so no single tool fixes it. You need to know whether mailbox providers trust your domain, whether authentication is set up correctly, whether emails actually land in the inbox, and whether your list is clean. The tools below are grouped by which of those questions they answer.
Resources
Disclosure up front: Loops is our product. It appears once in this list, in the ESP section, and we explain exactly where it fits and where it does not. Pricing below is approximate as of July 2026.
Quick comparison
Pricing is approximate as of July 2026. Verify current pricing before relying on it.
The first ten tools diagnose. The last two are ESPs, because your ESP is what actually determines most of your deliverability: its IP pools, its queueing behavior, and how much authentication setup it automates.
1. Google Postmaster Tools
If you send to Gmail addresses, this is non-negotiable and free. It shows your domain and IP reputation, spam-rate trend, and authentication pass rates as Gmail actually sees them. Its weakness: data only appears at meaningful volume, updates lag by days, and it tells you that something is wrong, never what. Set it up before you have a problem so you have a baseline.
2. Microsoft SNDS
The Outlook and Hotmail equivalent. Cruder than Postmaster Tools: it reports on sending IPs rather than domains, so shared-IP senders see pool-level data. Still worth registering, because Microsoft reputation problems are otherwise invisible until support tickets arrive.
3. GlockApps
Sends your email to a seed list of real accounts across Gmail, Outlook, Yahoo, and others, then reports where it landed: inbox, promotions, spam, or missing. Good for spot-checking a big campaign before launch. Caveat: seed accounts behave differently from real engaged subscribers, so treat results as directional, not gospel.
4. Validity Everest
The enterprise option, built from Return Path and 250ok. It combines placement testing, reputation monitoring, and engagement analytics in one dashboard. It is the most complete view money can buy, and it is priced like it. Overkill below roughly a million sends a month.
5. Litmus
Primarily a rendering tool: previews across dozens of clients, plus spam-filter checks before send. If your deliverability problem is actually a content problem, like broken HTML or spammy structure, Litmus surfaces it. It will not diagnose reputation or infrastructure issues. Know that Litmus retired its entry plan in 2025; pricing now starts around $417 a month billed annually, which puts it in committed-email-team territory, not casual pre-send checks.
6. Mailtrap
Started as a staging inbox so dev teams stop emailing real users from test environments, and that is still what it does best. It has since added sending and deliverability reports. The testing sandbox is genuinely useful for SaaS teams; for production deliverability monitoring it is thinner than the dedicated tools above.
7. MXToolbox
The Swiss army knife: SPF, DKIM, DMARC, MX, and blocklist lookups in one place, free for manual checks. Paid plans add monitoring and alerts. Every team should bookmark it; most never need to pay.
8. EasyDMARC
DMARC rollout for teams without a deliverability engineer. Wizards for SPF, DKIM, and DMARC records, readable aggregate reports, and guided progression from monitoring to enforcement. The right first DMARC tool for most SaaS companies.
9. dmarcian
Deeper DMARC reporting and forensics than EasyDMARC, from one of the people who wrote the DMARC spec. Slightly steeper learning curve, more data. Pick one of the two; running both is redundant.
10. ZeroBounce
Verifies addresses before you send: it catches dead mailboxes, spam traps, and disposable domains. Cleaning a stale list before a re-engagement campaign is the single cheapest deliverability win available. Any of ZeroBounce, NeverBounce, or Emailable will do the job; ZeroBounce has the most generous free tier.
11. Postmark
The transactional benchmark. Strict shared pools, separate message streams for transactional and broadcast, and consistently strong inbox rates. If you only need transactional email, it is excellent. You will need a second product for marketing and lifecycle email.
12. Loops
Our product, so judge accordingly. Loops handles marketing, transactional, and lifecycle email in one platform and automates the infrastructure that usually goes wrong: DNS records are configured automatically, sending is queue-managed to protect domain reputation, and warmup is handled for you. It will not give you seed-list placement tests or DMARC forensics, which is why the tools above exist. If you want the diagnostic layer and the sending layer from one vendor, that is not us, and honestly it is not anyone.
How to choose
Everyone: Google Postmaster Tools plus MXToolbox. Free, ten minutes, do it today.
Rolling out DMARC: EasyDMARC, or dmarcian if you want depth.
Big campaign coming: GlockApps spot-check plus a ZeroBounce clean first.
Enterprise volume: Validity Everest.
Fixing deliverability by fixing the sender: pick an ESP that automates infrastructure. Postmark for transactional-only, Loops if you also send marketing and lifecycle email.
Frequently asked questions
What is the best free email deliverability tool?
Do I need a deliverability tool if my ESP handles deliverability?
Why are my emails going to spam even though I pass SPF and DKIM?
How often should I clean my email list?
Related guides: our email deliverability best practices guide and why emails go to spam.