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 |
| 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 | From $49/mo (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 |
Email verification tools, compared.
Most verifiers sell credit packs that never expire and a real-time API for signup forms. Unspam charges only for definitive answers, from $6.40 per 1,000 addresses, with 10 free checks a day; it has no real-time signup check and no native integrations yet.
| Tool | Best for | Free tier | Starts at |
|---|---|---|---|
| Unspam | Bulk lists and single checks with a status, reason and action per address, unknowns free, plus spam testing in the same plan | 10 checks a day, no signup | $5/mo Custom plan minimum, from $6.40 per 1,000 addresses |
| Kickbox | Pay-as-you-go email verifier with a real-time API, the Sendex quality score and a Threat Score for complainers. Its spam testing suite closed in 2024. | 100 free verifications | $5 one-time · 500 credits |
| NeverBounce | ZoomInfo's email verifier: real-time checks, a form widget, 80+ integrations and scheduled re-verification on its Growth plans. | Free list analysis and test credits, no card | $8 per 1,000 credits |
| Bouncer | EU-hosted email verification with catch-all resolution on Google and Microsoft, a toxicity check, and a separate Deliverability Kit. | 100 free credits at signup, no card | $8 one-time (1,000 credits) |
| Emailable | Fast list and real-time verification with a form widget, 21 native integrations and Inbox Reports on the same credits. | 250 free credits at signup, no card | $38 one-time (5,000 credits) |
| EmailListVerify | Low-cost bulk email verification with an inbox placement test, a blacklist check and an email finder on the same credits. | 100 free verifications at signup | €5 one-time (1,000 credits) |
| Verifalia | EU-hosted email verification with three quality levels, about 40 detailed status codes, daily free credits and SDKs in six languages. | 25 free credits a day, account required | $7.90 one-time (1,000 credits) |
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 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.
Email verification comparisons
Kickbox
Pay-as-you-go email verifier with a real-time API, the Sendex quality score and a Threat Score for complainers. Its spam testing suite closed in 2024.
Unspam vsNeverBounce
ZoomInfo's email verifier: real-time checks, a form widget, 80+ integrations and scheduled re-verification on its Growth plans.
Unspam vsBouncer
EU-hosted email verification with catch-all resolution on Google and Microsoft, a toxicity check, and a separate Deliverability Kit.
Unspam vsEmailable
Fast list and real-time verification with a form widget, 21 native integrations and Inbox Reports on the same credits.
Unspam vsEmailListVerify
Low-cost bulk email verification with an inbox placement test, a blacklist check and an email finder on the same credits.
Unspam vsVerifalia
EU-hosted email verification with three quality levels, about 40 detailed status codes, daily free credits and SDKs in six languages.
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.