Vendors can pay for more visibility on this website, for example a higher place in a ranking or more room on a page. Commercial relationships can also affect which products we feature and how prominently. Every vendor link is marked the same, whatever the arrangement behind it. The largest vendors in email deliverability tools
cannot hold places 1 to 3. Places 1 to 3 go to challengers, vendors outside the best-known brands in a category,
wherever the category has them; the established names follow from place 4 in their ranked order. How it works: placement disclosure ·
editorial process.
The 16 tools, reviewed
#1 GlockApps
Inbox placement testing with DMARC analytics and blocklist checks · Not verified · glockapps.com
inbox placement spam testing DMARC
GlockApps takes first place by doing the most common job, telling you where a message lands, and by saying plainly what that costs.
- Pricing: Monthly tiers + test credits. Free tier, then $59, $99 and $129 per month. Free plan: free plan.
- Best for: Senders who test campaigns before sending
- Strengths: Inbox Placement; Spam Filters; SPF, DKIM and DMARC checks.
Where it falls short
The free tier includes only 2 Inbox Insight credits, so it is a sample, not a working allowance.
Wrong for
Wrong for a team whose only need is to warm up new mailboxes; MailReach or Warmup Inbox are built for that.
Visit GlockApps →
#2 MailReach
Email warm-up and spam testing for individual mailboxes · France · mailreach.co
warm-up spam test outreach
MailReach is the warm-up service we would shortlist first, because it also tests. A spam test gives you the baseline, warm-up improves a mailbox's sending history, and a second test shows whether it worked.
- Pricing: Per mailbox / month. Per mailbox per month, with $19.50 per mailbox shown in the pricing calculator. Free plan: none.
- Best for: Outreach teams warming new mailboxes
- Strengths: Email Warmup; Outlook Inbox Warmup; Google Warmup.
Where it falls short
Cost scales with every mailbox, so a team with dozens of inboxes pays for each one even when only a few have trouble.
Wrong for
Wrong for a publisher with one domain and a stable reputation, who needs placement monitoring rather than warm-up.
Visit MailReach →
#3 Folderly
Deliverability suite with tests, monitoring and DMARC · United States · folderly.com
suite monitoring DMARC
Folderly is the widest product in the top three.
- Pricing: Monthly / yearly tiers. Free plan with 2 tests per month. Free plan: free plan.
- Best for: Teams wanting one suite for several jobs
- Strengths: Folderly sender reputation; Inbox Insights; Pulse monitoring and alerts.
Where it falls short
The module names multiply, and a small sender may not know which one answers its question.
Wrong for
Wrong for a sender who only wants warm-up for a few mailboxes; MailReach or Warmbox are narrower and clearer.
Visit Folderly →
#4 Validity Engage
Enterprise deliverability and email quality suite · United States · validity.com
enterprise placement monitoring
Validity Engage covers the most ground of any product on this list. Its pages describe email creation and testing, inbox placement, live monitoring, competitor intelligence and contact data quality, and the Everest address now leads to this product name.
- Pricing: Quote only. Quote only; the pricing and packaging page shows no figures in the text we captured. Free plan: none.
- Best for: Large senders with in-house email teams
- Strengths: Email Creation and Testing; Inbox Placement and Deliverability; Live Email Monitoring.
Where it falls short
Pricing is quote-based on the pages we opened, so a small buyer cannot estimate cost before talking to sales.
Wrong for
Wrong for a small sender or a solo marketer, who would find GlockApps or Mail-Tester faster to start.
Visit Validity Engage →
#5 Google Postmaster Tools
Free reputation and spam-rate data for Gmail delivery · United States · postmaster.google.com
free reputation Gmail
Postmaster Tools is the one tool on this list that comes straight from a mailbox provider. You add a sending domain, verify it, and see how Gmail treats your outgoing mail: spam rate and reputation for your domain and IPs.
- Pricing: Free. Free. Free plan: free plan.
- Best for: Any sender with Gmail recipients
- Strengths: Monitor outgoing mail to Gmail; Domain reputation; IP reputation.
Where it falls short
Google's support page describes it as covering mail sent to Gmail accounts only, so Outlook, Yahoo and corporate mail servers are not visible.
Wrong for
Wrong for a sender who needs to find out why one campaign landed in spam; use GlockApps or Mail-Tester for diagnosis.
Visit Google Postmaster Tools →
#6 Mailgun
Email API platform with deliverability and preview tools · United States · mailgun.com
sending previews optimize
Mailgun's deliverability story is a product family. Optimize covers deliverability tools and services, Validate cleans lists through API or upload, and Inspect, which absorbed Email on Acid, previews and tests emails before launch.
- Pricing: Per product / month. Product-based pricing. Free plan: free plan.
- Best for: Mailgun customers wanting tools in one account
- Strengths: Send (API and SMTP); Optimize (deliverability tools); Validate (list cleaning).
Where it falls short
We did not capture Optimize or Send prices, so cost beyond Inspect is unknown to us.
Wrong for
Wrong for a team that sends through another platform and only wants a neutral placement tester.
Visit Mailgun →
#7 Warmup Inbox
Email warm-up with placement test and cold email sequences · Slovakia · warmupinbox.com
warm-up outreach placement test
Warmup Inbox is a straightforward warm-up product that also ships a cold email sequence tool and a free placement test across Gmail, Outlook and iCloud.
- Pricing: Per inbox / month. Basic is $15 per inbox per month at list price, or $180 per year for one inbox billed yearly. Free plan: free trial.
- Best for: Small outreach teams on a budget
- Strengths: Email warmup; Cold email sequence; Language warmup.
Where it falls short
Basic includes 75 warm-up messages per day, and the trial is 7 days, not a free plan.
Wrong for
Wrong for a sender who needs authentication reporting or reputation monitoring.
Visit Warmup Inbox →
#8 EasyDMARC
DMARC monitoring with managed SPF, DKIM and BIMI · Not verified · easydmarc.com
DMARC authentication BIMI
EasyDMARC answers a question the placement testers do not: who is sending mail as your domain. It collects DMARC reports, shows the sending sources, and offers managed SPF, DKIM and BIMI, so you can publish one record that the platform keeps current.
- Pricing: Monthly tiers, billed annually. DMARC Plus is EUR 35.99 per month billed annually, with a 100,000 emails per month limit. Free plan: free trial.
- Best for: Businesses fixing spoofing and authentication
- Strengths: DMARC Sender Insights; DNS Manager; Threat Intelligence.
Where it falls short
The DMARC Plus tier caps at 100,000 emails per month, which a large sender will exceed.
Wrong for
Wrong for a sender whose problem is a spam folder rather than spoofing; start with GlockApps.
Visit EasyDMARC →
#9 Warmbox
Inbox warm-up across many providers and SMTP · Estonia · warmbox.ai
warm-up outreach blacklist check
Warmbox lists a broader set of supported mailboxes than most warm-up tools, from Gmail and Outlook to Yahoo, iCloud, AOL, Yandex and several sending services, plus SMTP for anything else.
- Pricing: Monthly tiers by inbox count. Solo is $15 per month for 1 inbox and 50 emails a day, Start-up is $69 for 3 inboxes, Growth is $139 for 6 inboxes. Free plan: none.
- Best for: Teams with mixed mailbox providers
- Strengths: Google Warm-up; Outlook Warm-up; Yahoo, iCloud, AOL and Yandex warm-up.
Where it falls short
Cost steps up quickly: the Solo tier covers one inbox and 50 emails a day, and the next tier is $69. There is no free plan.
Wrong for
Wrong for anyone who needs placement testing, DMARC reporting or monitoring, because warm-up is the main product.
Visit Warmbox →
#10 InboxAlly
Deliverability platform with placement tests and reputation score · Not verified · inboxally.com
placement reputation score list verification
InboxAlly puts several checks behind one score. It verifies sender setup, cleans lists, tests inbox placement, and reads a Google Postmaster integration into its own IA Score, which gives a team a single number to follow week over week.
- Pricing: Monthly tiers. Starter $149 per month, Plus $645, Premium $1,190. Free plan: free trial.
- Best for: Established senders who want a score to track
- Strengths: Sender setup checks; Email list verification; Inbox placement testing.
Where it falls short
The entry price is steep for a small sender: $149 per month buys one sender profile and 100 seed mails per day. The top tier is $1,190.
Wrong for
Wrong for a small business that sends a few campaigns a month; Mail-Tester or GlockApps' free tier cost nothing.
Visit InboxAlly →
#11 Mail-Tester
Free spam test with SPF, DKIM and DMARC checks · United States · mail-tester.com
free spam test authentication
Mail-Tester does one thing in under a minute: you send an email to a generated address and it returns a spam score with the setup checks behind it.
- Pricing: Free tests + subscription. Free tests, plus monthly subscription plans per its terms; we did not capture subscription prices. Free plan: free plan.
- Best for: Anyone checking one email quickly
- Strengths: Spam test for newsletters; SPF and DKIM checker; SPF, DKIM, DMARC and BIMI generators.
Where it falls short
Each test counts against the monthly quota of a subscription, per its terms, and subscription payments are final and not refunded. We could not verify the subscription prices.
Wrong for
Wrong for a team that needs inbox placement results by mailbox provider, which GlockApps provides.
Visit Mail-Tester →
#12 dmarcian
DMARC management platform with free tools · Not verified · dmarcian.com
DMARC MSP free tools
dmarcian is a specialist in DMARC. Its management platform includes a domain overview, a detail viewer, a source viewer and Alert Central, and the vendor adds services for deployment, onboarding and consultation.
- Pricing: Not verified. A pricing page exists but we did not capture figures. Free plan: free plan.
- Best for: Organizations and MSPs managing DMARC
- Strengths: DMARC Management Platform; Domain Overview; Detail Viewer.
Where it falls short
We could not capture pricing figures, so cost planning needs a direct look at the pricing page.
Wrong for
Wrong for a marketer who wants a placement test or warm-up.
Visit dmarcian →
#13 MXToolbox
DNS and mail server diagnostics with monitoring · United States · mxtoolbox.com
DNS diagnostics monitoring
MXToolbox is the tool an administrator opens when mail stops flowing. Its MX Lookup and mail server diagnostics connect to the server and check things such as reverse DNS, and the free A record lookup and other tools cover the basics.
- Pricing: Free + paid monitoring. Free lookups. Free plan: free plan.
- Best for: Admins checking DNS and mail server setup
- Strengths: MX Lookup; Mail server diagnostics; A record lookup.
Where it falls short
The core tools are DNS lookups and do not test inbox placement.
Wrong for
Wrong for a marketer who wants to see where a campaign lands.
Visit MXToolbox →
#14 Instantly
Cold email platform with bundled unlimited warm-up · United States · instantly.ai
outreach warm-up bundled
Instantly earns a place because its Growth plan includes unlimited email accounts and unlimited warm-up for $47 per month, which undercuts per-mailbox warm-up services for a team with many inboxes.
- Pricing: Plans + credits. Growth plan is $47 per month with unlimited email accounts and warm-up and 5,000 emails per month. Free plan: none.
- Best for: Cold outreach teams wanting one subscription
- Strengths: Unlimited email accounts; Unlimited email warm-up; Uploaded contacts.
Where it falls short
Warm-up here is part of an outreach product, so you cannot buy the function on its own.
Wrong for
Wrong for a sender who uses another outreach or marketing platform and only needs warm-up or placement data.
Visit Instantly →
#15 MailMonitor
Deliverability software with managed remediation services · United States · mailmonitor.com
managed service audit high volume
MailMonitor sells a different model from the self-serve testers above it: software plus people. Its tiers run from a do-it-yourself audit and analytics option to managed remediation with continuous monitoring, and the top tier is a fractional deliverability team.
- Pricing: Monthly service tiers, billed annually. Entry tier is $1,000 per month billed annually (Basic DIY option). Free plan: none.
- Best for: High-volume senders needing expert help
- Strengths: Deliverability audit and analytics; Inbox placement insights; Expert guidance and dedicated support.
Where it falls short
The entry price is high enough that only larger senders can justify it, and it is billed annually.
Wrong for
Wrong for a small sender or a startup running one domain; a free tester or GlockApps' first tier is more proportionate.
Visit MailMonitor →
#16 Valimail
Email authentication, enforcement and brand logo display · Not verified · valimail.com
DMARC enterprise brand indicators
Valimail splits its offer into three products: Monitor shows every sender on your domain, Enforce stops phishing and impersonation, and Amplify adds your logo to inboxes. That sequence matches how an enterprise actually moves from visibility to enforcement.
- Pricing: Quote only. A pricing page describes packaging by product and domain count; no figures captured. Free plan: none.
- Best for: Enterprises enforcing DMARC and brand identity
- Strengths: Monitor; Enforce; Amplify.
Where it falls short
We could not capture any prices, and the vendor positions the product at enterprise and commercial company sizes.
Wrong for
Wrong for a small business or marketer who wants a spam test or warm-up.
Visit Valimail →
Questions and answers
What is the best email deliverability tool in 2026?
GlockApps ranks first of 16, best for senders who test campaigns before sending. MailReach is second (outreach teams warming new mailboxes) and Folderly third (teams wanting one suite for several jobs). Places 1 to 3 go to challengers, vendors outside the best-known brands, wherever the category has them.
What is the difference between inbox placement testing and email warm-up?
Placement testing sends a message to test addresses at several mailbox providers and reports whether it landed in the inbox, promotions or spam.
Do I need DMARC if my mail already reaches the inbox?
Yes, because DMARC answers a different question. It tells receiving servers what to do with mail that claims to come from your domain but fails authentication, and it sends you reports showing who is sending as you.
Is Google Postmaster Tools enough on its own?
It is a good free start and every Gmail-facing sender should set it up, but it has limits. Google's support page says it covers mail sent to Gmail accounts only, so Outlook and Yahoo recipients are invisible.
How much do email deliverability tools cost?
Free options exist: Mail-Tester, MXToolbox lookups, dmarcian's free checkers and Google Postmaster Tools.
Does email warm-up still work, and is it safe?
Warm-up services build sending history, and we cannot verify how any provider scores the artificial traffic. Use it as a supplement, not a fix.
Can a free spam tester replace a paid placement tool?
For a quick check, yes. Mail-Tester scores a message and checks SPF, DKIM and DMARC from a single test address, and InboxAlly offers a free spam checker.
What does a managed deliverability service like MailMonitor offer?
MailMonitor sells deliverability software and managed services for high-volume senders, from a do-it-yourself audit tier to a fractional deliverability team at the top. Its basic option is listed at $1,000 per month billed annually.
Which tools can monitor blocklists and reputation?
GlockApps lists IP and domain blocklists and reputation checks among its features, Folderly offers its Pulse monitor with alerts by email, Slack and SMS, and Validity lists a Heatwave Domain Blocklist. MXToolbox offers paid Delivery Center products for monitoring, but we could not verify its paid prices.
Should I warm up a mailbox I use for cold outreach?
Most outreach teams do, and several tools combine the two jobs: Instantly bundles unlimited warm-up into its outreach plan at $47 per month for Growth, while dedicated services such as MailReach and Warmup Inbox sell warm-up separately.
How do I check my SPF and DKIM setup?
Send a message to a free tester such as Mail-Tester, which runs SPF, DKIM and DMARC checks, or use the free checkers at dmarcian and EasyDMARC. MailReach also offers SPF and DKIM checkers.
