Free — no signup to start

Know exactly why your emails land in spam — and fix it in minutes.

SenderSuccess tests your authentication, content, and sender reputation the moment you hit send — then tells you precisely what to change, not just what's wrong.

No credit card Results in seconds Real DNS, real spam engine
Send an email to this address from the account you want to test
generating…
This address is single-use and expires in 30 minutes.
Checks the same signals mailbox providers do
SPFDKIMDMARCSpamhausBarracudaSORBSSpamCop
The cost of the spam folder

An email that doesn't land is worse than one you never sent.

Every bounce or spam-foldered email is a customer who never got your message — no error, no bounce notice back to you, just silence on the other end.

Deliverability compounds. Each complaint, each stale list, each misconfigured record chips away at the sender reputation every future email depends on.

Finding out after a launch is too late. Testing before you send is the only way to actually know — not guess.

01 — Test in seconds

One email in. One clear score out.

Generate a unique test address, send a real email from your real sending setup — your ESP, your CRM, your own mail server — and get a composite SenderSuccess Score across four categories: Authentication, Content, Compliance, and Reputation. Every check shown, every point explained.

83
Authentication27/30
Content26/30
Compliance15/20
Reputation15/20
02 — Reputation, monitored

Know the moment your IP gets blacklisted — not a week later.

Every test checks your sending IP against Spamhaus, Barracuda, SORBS, and SpamCop in real time — plus PTR/forward-confirmed reverse DNS, MX records, and HELO validity. No simulated results: real DNS lookups, every time.

Coming soon: add multiple domains to your account and monitor their score history over time, from every test you run.
Spamhaus ZENNot listed
Barracuda RBLNot listed
SORBSNot listed
Reverse DNS (PTR)FCrDNS OK
03 — Content, inspected

Spam filters read your email like a machine. So do we.

A real local spam-scoring engine, not a guess — plus spam-trigger phrase detection, link-to-text ratio, image-to-text ratio, and checks for broken, shortened, or IP-literal links. The same patterns that get real mail filtered.

✓
Spam-trigger phrases5/5
!
Link count & ratio3/5
✓
Image-to-text ratio3/3
04 — Fixes, not fortune cookies

Specific beats generic, every time.

Every failed or borderline check ships with an exact, technical suggestion built from your own real evidence — not boilerplate advice you'd find in a 2011 blog post.

Generic advice
"Improve your SPF record."
SenderSuccess
"Your SPF record has 12 DNS lookups, exceeding the 10-lookup limit — flatten it by removing unused include: mechanisms."
Built for anyone who hits send

Wherever email is mission-critical, SenderSuccess has a seat at the table.

Email marketers

You've got one shot at a product launch. Test the exact template and sending domain a week out, not after open rates already tanked.

SaaS companies

New customer, new sending subdomain, new SPF/DKIM setup — verify every domain your platform sends from before it reaches a real inbox.

Agencies

Ten clients, ten sending domains, ten different reputations to track. Run one test per domain and know instantly which ones need attention.

Sales & outreach teams

Cold email lives or dies on inbox placement. Check every new sending alias before a rep burns their first send on it.

IT & ops teams

Migrated mail servers, rotated an IP, changed an SPF include? Confirm nothing broke in the two minutes it takes to send a test.

Somewhere in between?

If your business depends on email reaching an inbox, this is built for you too. Run a test — it takes less time than reading this card.

Built to be trusted with your infrastructure

Self-hosted. Your data stays yours.

Not a black box

Runs on infrastructure you control. Test emails and results live on your own server, not a third party's.

Nothing simulated

Every check is a real DNS lookup or a real local spam-engine score — never a mocked or cached result.

Free to start

No credit card for your first test. Create a free account when you want more.

What early users say

Placeholder testimonials — sample content, not real customers

"We caught a broken DKIM selector on a new subdomain before a single campaign went out. That's a save I don't want to calculate the cost of."
Priya Anand
Head of Lifecycle Marketing, Northwind Outreach*
"Our agency runs a SenderSuccess check on every client domain before onboarding. It's the fastest 'is this actually going to work' answer we've found."
Marcus Webb
Deliverability Lead, Cascade Metrics*
"I don't need to know what a DMARC alignment mode is — SenderSuccess just tells me what to change, in plain English."
Elena Torres
Founder, Fieldstone Agency*
* Placeholder names and companies for design purposes — to be replaced with real customer testimonials.

Frequently asked questions

Is the test really free?

Yes — generate a test address (or paste a raw email) and get your first SenderSuccess Score with no signup and no credit card. Create a free account for unlimited daily tests and full reports by email.

What exactly does the score measure?

Four categories: Authentication (SPF, DKIM, DMARC, PTR, MX, HELO), Content (spam-engine score, trigger phrases, link and image ratios), Compliance (unsubscribe link/header, physical address), and Reputation (real-time blacklist checks).

Do I need to install anything?

No. Either send a real email to a generated test address from whatever system you already send from, or paste a complete raw message you already have — the report appears in your browser either way.

Is my test email stored anywhere public?

No — each test is private to the account (or anonymous session) that created it.

Can I test my whole domain, or just one email?

Every test evaluates one message end-to-end — send from every sending source you use (marketing platform, transactional service, personal client) to get a full picture of your domain's deliverability.

Stop guessing why your emails don't land.

Run your first SenderSuccess test free — right now, above.

↑ Back to the test