The best email deliverability tools in 2026, compared.
Honest, side-by-side comparisons: pricing, features, and who each tool actually fits. Based on public product pages and real user reviews, updated as tools change.
The best email deliverability testing tools in 2026 are Unspam, Mail-Tester, GlockApps, MailReach, and EasyDMARC. Unspam is the only one that combines a free spam score, real inbox-placement testing across Gmail, Outlook, Yahoo and more, client previews, and an AI attention heatmap in a single plan, free to start with no card and usage-priced from a $5 monthly minimum. Mail-Tester is the classic quick spam-score check, GlockApps leads on seed-list placement and DMARC analytics, MailReach focuses on inbox warmup, and EasyDMARC owns continuous DMARC, SPF, and DKIM monitoring. The table below compares free tiers, starting prices, and what each tool is best for.
These pages compare one tool at a time. For the whole market grouped by the job each tool does, with current pricing, read the roundup of every deliverability tool.
| Tool | Best for | Free tier | Starts at |
|---|---|---|---|
| Unspam | Free spam score, inbox placement, client previews and an AI heatmap in one plan | Free plan, no card | $5/mo minimum, usage-priced |
| GlockApps | Seed-list placement testing with DMARC analytics and IP-reputation monitoring. | Free: 2 test credits | $59/mo billed annually |
| Kickbox | Pay-as-you-go email verification. Its spam testing and placement suite was discontinued in 2024. | 100 free verifications | $5 one-time · 500 credits |
| Mail-Tester | The classic send-to-address spam-score checker built on SpamAssassin. | Free: 3 tests/day | $10/mo |
| MailGenius | Pre-send spam testing with authentication and content checks, priced on monthly plans with test quotas. | Free: basic spam test, no account | $29/mo |
| MailReach | Automated mailbox warmup paired with credit-based spam and placement tests. | Free spam test only | $25/mailbox/mo |
| Warmy | AI-driven mailbox warmup with placement tests and DNS/auth monitoring. | 7-day free trial | Quoted on request (volume-based) |
| MXToolbox | Email-infrastructure diagnostics: DNS, blacklist, and auth lookups plus a paid Delivery Center. | Free lookup tools | $129/mo |
| Folderly | B2B inbox warmup and placement monitoring by Belkins, priced per mailbox. | Free: 2 placement tests/mo | $96/mailbox/mo annual |
| Validity Everest | Enterprise placement testing and reputation monitoring, now sold only inside the Validity Engage platform. | See site | Custom (no published price) |
| Litmus | Email QA and previews across 100+ clients, sold only inside the Validity Engage platform. | No trial published | Not published (quote only) |
| Mailtrap | A developer email-testing sandbox and sending API: capture test emails, check spam score and HTML, then send via SMTP. | Free: 50 sandbox test emails/mo | $14/mo billed annually (Email Sandbox Basic) |
| ZeroBounce | Large-scale email verification with a bundled deliverability suite (placement, warmup, blacklist and DMARC monitoring) on its ONE plan. | Free: 100 verification credits/mo | $39 one-time (2,000 verification credits) |
| Email on Acid | Cross-client email rendering previews and a pre-send QA checklist (Campaign Precheck), now sold as Mailgun Inspect by Sinch. | Free trial only, no free plan | $99/mo |
| Mailgun | Email sending platform and API by Sinch, with the Optimize add-on for deliverability testing. | Send: free (100 emails/day). Optimize: 1-month trial | Send from $15/mo; Optimize from $49/mo |
DMARC monitoring tools, compared.
Each tool prices report monitoring its own way: per domain, by email volume, or by quote. Unspam reads aggregate reports at $6 per domain per month, first domain free; most of the tools below also host records and send alerts.
| Tool | Best for | Free tier | Starts at |
|---|---|---|---|
| Unspam | Aggregate report monitoring with named senders and policy readiness, first domain free | First domain free on the Custom plan | $5/mo Custom plan minimum, then $6 per domain per month |
| EasyDMARC | Email authentication platform that processes DMARC reports and hosts DMARC, SPF, DKIM, BIMI and MTA-STS records. | Not on the pricing page; help centre: 1 domain after trial | $35.99/mo billed annually |
| dmarcian | A hosted DMARC management platform that turns aggregate and forensic reports into views by sending source, sold with deployment services. | Personal: free for non-business use, 2 domains, 1,250 emails/mo | $24/mo (Basic), or $19.99/mo billed yearly |
| PowerDMARC | A DMARC platform that processes aggregate and forensic reports and hosts DMARC, SPF, DKIM, BIMI and MTA-STS records, priced by email volume. | Free for personal domains: 1 domain, 10,000 emails, 10 days of history | $8/mo (Basic, 50,000 emails, monthly billing) |
| Valimail | A DMARC-as-a-service platform that hosts DMARC, SPF and DKIM through DNS delegation, with a free reporting tier called Monitor. | Monitor: free reporting, no card, cannot change policy | $250 per domain per year (Essentials) |
| Red Sift OnDMARC | A DMARC platform from Red Sift that hosts DMARC, SPF, DKIM, BIMI and MTA-STS records and guides domains to enforcement. | 14-day trial, no free plan | $9/mo billed annually (Express), $12 billed monthly |
| Sendmarc | A DMARC management platform that configures, monitors and enforces DMARC, SPF and DKIM, sold direct and through MSPs. | Free Basic Reporting: 1 domain, 5k emails, 21 days history | Quote only |
| DMARCLY | An SPF, DKIM and DMARC monitoring service priced by domain count and message volume, with hosted SPF on higher plans. | 14-day trial, no free plan | $17.99/Month (Professional, up to 2 domains) |
| Mimecast DMARC Analyzer | Mimecast's cloud service for DMARC setup, reporting and enforcement, sold by quote standalone or inside the Mimecast suite. | 14-day trial, no free plan | Quote only |
| Cloudflare DMARC Management | A Cloudflare dashboard feature that receives DMARC aggregate reports for domains on Cloudflare DNS and shows each sending source. | No separate charge, included on all Cloudflare plans | No separate charge; requires Cloudflare DNS |
| DMARC Report | DMARC reporting and monitoring service by DuoCircle, with hosted DMARC and MTA-STS, alerts, and a free plan for one domain. | Core: free, 1 domain, 10,000 messages/mo | $25/mo (Guard, 5 domains) |
| DMARC Digests | Postmark's DMARC report service: a free weekly email digest, and a paid dashboard with longer history and team access. | Free Postmark tool: weekly email digest, 7 days of history | $14/mo per domain |
Read the full comparison
GlockApps
Seed-list placement testing with DMARC analytics and IP-reputation monitoring.
Unspam vsKickbox
Pay-as-you-go email verification. Its spam testing and placement suite was discontinued in 2024.
Unspam vsMail-Tester
The classic send-to-address spam-score checker built on SpamAssassin.
Unspam vsMailGenius
Pre-send spam testing with authentication and content checks, priced on monthly plans with test quotas.
Unspam vsMailReach
Automated mailbox warmup paired with credit-based spam and placement tests.
Unspam vsWarmy
AI-driven mailbox warmup with placement tests and DNS/auth monitoring.
Unspam vsMXToolbox
Email-infrastructure diagnostics: DNS, blacklist, and auth lookups plus a paid Delivery Center.
Unspam vsFolderly
B2B inbox warmup and placement monitoring by Belkins, priced per mailbox.
Unspam vsValidity Everest
Enterprise placement testing and reputation monitoring, now sold only inside the Validity Engage platform.
Unspam vsLitmus
Email QA and previews across 100+ clients, sold only inside the Validity Engage platform.
Unspam vsMailtrap
A developer email-testing sandbox and sending API: capture test emails, check spam score and HTML, then send via SMTP.
Unspam vsZeroBounce
Large-scale email verification with a bundled deliverability suite (placement, warmup, blacklist and DMARC monitoring) on its ONE plan.
Unspam vsEmail on Acid
Cross-client email rendering previews and a pre-send QA checklist (Campaign Precheck), now sold as Mailgun Inspect by Sinch.
Unspam vsMailgun
Email sending platform and API by Sinch, with the Optimize add-on for deliverability testing.
DMARC monitoring comparisons
EasyDMARC
Email authentication platform that processes DMARC reports and hosts DMARC, SPF, DKIM, BIMI and MTA-STS records.
Unspam vsdmarcian
A hosted DMARC management platform that turns aggregate and forensic reports into views by sending source, sold with deployment services.
Unspam vsPowerDMARC
A DMARC platform that processes aggregate and forensic reports and hosts DMARC, SPF, DKIM, BIMI and MTA-STS records, priced by email volume.
Unspam vsValimail
A DMARC-as-a-service platform that hosts DMARC, SPF and DKIM through DNS delegation, with a free reporting tier called Monitor.
Unspam vsRed Sift OnDMARC
A DMARC platform from Red Sift that hosts DMARC, SPF, DKIM, BIMI and MTA-STS records and guides domains to enforcement.
Unspam vsSendmarc
A DMARC management platform that configures, monitors and enforces DMARC, SPF and DKIM, sold direct and through MSPs.
Unspam vsDMARCLY
An SPF, DKIM and DMARC monitoring service priced by domain count and message volume, with hosted SPF on higher plans.
Unspam vsMimecast DMARC Analyzer
Mimecast's cloud service for DMARC setup, reporting and enforcement, sold by quote standalone or inside the Mimecast suite.
Unspam vsCloudflare DMARC Management
A Cloudflare dashboard feature that receives DMARC aggregate reports for domains on Cloudflare DNS and shows each sending source.
Unspam vsDMARC Report
DMARC reporting and monitoring service by DuoCircle, with hosted DMARC and MTA-STS, alerts, and a free plan for one domain.
Unspam vsDMARC Digests
Postmark's DMARC report service: a free weekly email digest, and a paid dashboard with longer history and team access.