Test inbox placement across all major email providers
See exactly where your emails land at Gmail, Microsoft O365, Hotmail, Yahoo, Apple Mail, and Zoho. Catch spam folder issues before your subscribers never see your message.
Starting at $19.99/mo — unlimited inbox placement tests · REST API included
Test inbox placement across all major email providers
Our email delivery test sends your message to real seed addresses across every major ISP. Within minutes, you see exactly where each email landed — primary inbox, spam folder, or promotions tab.
No code. No complicated setup. Send an email, get real placement data from real inboxes. Or use the REST API to integrate testing directly into your sending workflow.
We provide over 70 unique seed email addresses spread across Gmail, Microsoft O365, Hotmail, Yahoo, Apple Mail, and Zoho — with multiple seeds per provider to reveal how ISPs inconsistently filter the same email.
Send each seed address a separate email exactly as you would in a real campaign. Use your actual ESP, real sending domain, and live content. Do not CC or BCC multiple seeds.
See where each email landed — inbox, spam, or promotions tab. Review header analysis, SCL scores, ICL data, and get actionable recommendations. Export as CSV or PDF, or retrieve results programmatically via the API.
More than a simple spam score. Real inbox placement data from real mailboxes at every major provider — with a REST API for teams that need to automate.
Test across 70+ seed addresses at Gmail, Yahoo, Hotmail, Microsoft O365, Apple Mail, and Zoho. ISPs filter inconsistently — testing many seeds per provider reveals the true distribution of your inbox placement.
Examine full email headers including Microsoft's Spam Confidence Level (SCL), Apple's Inbox Confidence Level (ICL), and authentication results for SPF, DKIM, and DMARC per seed address.
Automate inbox placement testing via the Campaign Cleaner REST API. Create tests, retrieve per-seed results including inbox rate, spam rate, SPF status, and sender IP — all programmatically. One API credit per test.
Upload your email for analysis and fine-tune content to improve inbox placement. Fix spam triggers, optimize text-to-image ratios, and clean up HTML issues before sending.
Export complete inbox placement results as CSV or PDF. Share deliverability data with your team, track performance over time, and build a historical improvement record.
Every inbox placement test automatically runs a full mail tester analysis alongside your seed results — checking SPF, DKIM, DMARC authentication, spam scoring, and blacklist status in one test. Most tools make you run these separately.
Every major ISP uses different signals to decide inbox vs. spam. Our test shows you where your email landed and what's in the headers.
Our test tells you if your email hit the inbox or spam at Gmail. To understand why, create a free account on Google Postmaster Tools for domain reputation, IP reputation, spam rates, and authentication pass/fail data.
DOMAIN + IP REPOur test extracts O365's SCL and BCL scores from the headers independently. An email can land in the inbox at O365 but hit junk at Hotmail. For deeper IP reputation data, check Microsoft SNDS.
SCL + BCL IN HEADERSHotmail and O365 share Microsoft's infrastructure but maintain separate scoring and reputation databases. Our test extracts Hotmail's SCL and BCL scores from the headers independently, which is why we test both separately.
SCL + BCL IN HEADERSApple uses an ICL (Inbox Confidence Level) score based on engagement, authentication, and delivery history. We report where your email landed at Apple Mail and surface any ICL data available in the headers.
ICL SCORINGOur test shows inbox vs. spam placement and header details at Yahoo. For deeper insight into complaint rates and delivery performance, sign up for Yahoo Sender Hub.
CFL + SENDER HUBZoho applies strict authentication-based filtering with its own spam detection. Especially important for B2B senders whose recipients use Zoho Workplace — a provider often overlooked by other inbox placement tools.
AUTH + FILTERINGYour content, your data, your infrastructure, and your reputation are all either working for you or against you, depending on how you manage them.
Integrate email deliverability testing directly into your sending platform, CI/CD pipeline, or email marketing workflow. Two endpoints, JSON in and out, API key authentication.
Initiate a new inbox placement test. Returns a unique job_id and the full list of seed addresses to send your campaign to, including the monitoring address.
test_name in the request bodysend_to seed address arrayX-CC-API-Key request headerPoll for results using your job_id. Results populate as seed mailboxes receive your campaign. Call repeatedly until status: Completed.
Processing or CompletedX-CC-API-Key request header# Step 1: Create the inbox test — receive your seed address list curl --request POST \ --url https://api.campaigncleaner.com/v1/create_inbox_test \ --header 'X-CC-API-Key: your_api_key' \ --header 'Content-Type: application/json' \ --data '{"test_name": "Q2 Campaign Pre-send Check"}' # Returns job_id and send_to array. Send your campaign to every address in send_to. # Step 2: Poll for results after sending your campaign curl --request POST \ --url https://api.campaigncleaner.com/v1/get_inbox_test_results \ --header 'X-CC-API-Key: your_api_key' \ --header 'Content-Type: application/json' \ --data '{"job_id": "12345"}' # Returns per-seed placement (Inbox/Spam/Pending), inbox_rate, spam_rate, SPF status # Poll until status: "Completed"
Email deliverability refers to whether your message actually arrives in a recipient's inbox — not just whether the server accepted it. You can have a 99% delivery rate and still suffer from terrible deliverability if most of your emails are landing in spam folders or promotions tabs where subscribers never see them.
That's why running an email delivery test is critical before every major campaign. An inbox placement test sends your email to real seed addresses at providers like Gmail, Microsoft O365, Hotmail, Yahoo, Apple Mail, and Zoho, then reports back exactly where each message landed. This is fundamentally different from a spam score checker, which only analyzes your content for red flags. Real-world placement data tells you what's actually happening.
A common misconception is that spam filtering is binary — your email either goes to the inbox or it doesn't. In reality, ISPs distribute emails inconsistently. The same email sent to the same provider might reach the inbox for 30% of recipients and land in spam for the remaining 70%. This distribution depends on individual engagement history, sender reputation at the IP and domain level, authentication results, and the content itself.
This is why testing with many seed addresses per provider is essential. A single test email to one Gmail address doesn't tell you the full story. Our inbox placement tester uses over 70 seeds across ISPs — including separate seeds for Microsoft O365 and Hotmail, which can filter differently despite sharing Microsoft's infrastructure — to reveal the actual distribution of your deliverability.
These terms sound similar but mean very different things. Email delivery means the recipient's mail server accepted your message — it didn't bounce. Email deliverability is about what happens next: did the message reach the primary inbox, get sorted into a secondary tab, or get buried in the spam folder? You need both, but deliverability is what determines whether anyone actually reads your email.
Email deliverability is influenced by three broad categories. Technical factors include your IP reputation, domain authentication (SPF, DKIM, DMARC), and whether your sending infrastructure is properly warmed up. Sending factors cover your domain and sender reputation, sending patterns, list hygiene, and how recipients have historically engaged with your emails. Content factors include subject line quality, HTML structure, text-to-image ratio, link reputation, and whether your message contains known spam trigger words or phrases.
No single factor determines placement. ISPs use machine learning models that weigh hundreds of signals together. That's why a comprehensive email delivery test — one that checks placement across Gmail, Microsoft O365, Hotmail, Yahoo, Apple Mail, and Zoho, analyzes headers, and evaluates content — gives you the most complete picture of what's happening with your emails.
DMARC (Domain-based Message Authentication, Reporting, and Conformance), defined in RFC 7489, is now required by Gmail, Yahoo, and Microsoft for bulk senders. A properly configured DMARC policy tells mailbox providers what to do with emails that fail SPF or DKIM checks — reject them, quarantine them, or let them through. Without DMARC, you have no control over how providers handle unauthenticated mail claiming to come from your domain, and your inbox placement will suffer.
Our email deliverability test checks your DMARC alignment as part of the full header analysis, so you can see whether authentication is passing or failing before your real campaign goes out.
For teams that send at volume or want to integrate deliverability testing into their workflow, the REST API provides two endpoints: create_inbox_test initiates a test and returns the seed address list, and get_inbox_test_results retrieves per-seed placement data once your campaign has been sent. Poll using your job_id until status returns Completed. Results include per-seed placement, inbox rate, spam rate, SPF status, and sender IP — everything you need to catch deliverability issues before they reach your real audience.
The best practice is to test before every significant campaign send. Beyond that, you should run an email deliverability test whenever you change ESPs or sending infrastructure, switch to a new sending domain or IP, notice a drop in open rates or engagement, make significant changes to your email template or content, or increase your sending volume substantially. Regular testing catches problems early — before they damage your sender reputation or cost you revenue from undelivered messages.
An email deliverability test sends your email to seed addresses at major providers like Gmail, Microsoft O365, Hotmail, Yahoo, Apple Mail, and Zoho to check whether it lands in the inbox, spam folder, or promotions tab. It helps you diagnose issues before sending to your real audience.
We provide over 70 seed addresses across major ISPs. You send your email to these addresses separately. Our system checks where each email landed: primary inbox, spam folder, or a secondary tab. Results include full header analysis, ISP-specific scores like Microsoft's SCL and Apple's ICL, and actionable recommendations.
Yes. The Email Deliverability Test provides a REST API with two endpoints: create_inbox_test to initiate a test and receive your seed address list, and get_inbox_test_results to poll for per-seed placement results including inbox rate, spam rate, SPF status, and sender IP. Authentication is via API key in the request header. One credit is deducted per test created. Full documentation is at docs.campaigncleaner.com.
Emails land in spam due to a combination of factors: poor IP or domain reputation, missing authentication (SPF, DKIM, DMARC), spammy content triggers, low engagement rates, blacklist listings, or sudden spikes in sending volume. Your content, your data, your infrastructure, and your reputation are all either working for you or against you depending on how you manage them.
Our inbox placement test covers Gmail, Microsoft O365, Hotmail, Yahoo Mail, Apple Mail (iCloud), and Zoho Mail, with over 70 seed addresses spread across providers. We are continuously expanding coverage and adding new seeds.
Inbox placement testing starts at $19.99 per month, giving you access to the full Inbox Placement Test Center with 70+ seed addresses, email header analysis, REST API access, downloadable CSV and PDF reports, and content optimization through Campaign Cleaner. Need hands-on help? You can also schedule an email deliverability consultation.
A spam score checker analyzes your email content for red flags. An inbox placement test actually sends your email to real seed inboxes and reports where it lands. This tool provides real-world placement data plus header analysis including SCL, BCL, and ICL scores — giving you the complete picture that a content-only checker cannot.
Email delivery means the recipient's mail server accepted your email — it did not bounce. Email deliverability is whether your email reached the inbox or got filtered into spam. You can have 100% delivery but terrible deliverability if every email goes to junk. Our test measures actual deliverability.
Yes. Download your complete inbox placement test results as a CSV or PDF report. You can also retrieve results programmatically via the REST API. Share data with your team, track deliverability over time, and keep records of your improvements.
This tool is powered by Campaign Cleaner. When you click "Get Started," you will be taken to Campaign Cleaner's registration page to create your account and select the inbox testing subscription at $19.99/mo. Once registered, you will have immediate access to the Inbox Placement Test Center and API documentation.