Track spam scores over time
Compare spam scores across repeat tests and spot changes after a new template, sender or ESP. Use the test history to see whether your fixes reduced spam risk.
A Folderly alternative for your next campaign.
See where your campaign lands, fix what needs attention and review the email before send day. MailSlurp brings inbox placement, device previews and content checks together.
Trusted by teams at
See where every provider puts your email.
Gmail may put a campaign in Promotions while Yahoo sends it to spam. See each account's result, then inspect content and sender-domain findings to decide what to fix before your next send.
Test your email
Analyze domain health
Check SPF, DKIM, DMARC and spam blocklists alongside inbox placement. Spot authentication problems and blocklist findings before your next campaign.
Connect your ESP directly
Connect your sending service and schedule regular placement tests. Send through your own ESP, keep your real sender and campaign content, and review the results in MailSlurp.
Watch a real placement test.
Follow a test from its seed list to the provider report. See how MailSlurp connects the email you sent with inbox and spam outcomes, then keeps the findings ready for review.
Follow the walkthroughCatch the change before your audience does.
Schedule regular tests through your sending service and catch a drop in inbox placement. Compare runs, open a sender's history and identify the provider that changed.
Run a manual check before a campaign, set up recurring tests or trigger a run through the API. Your team can review every result and investigate spam scores in the web dashboard.
Choose how you test
Example test history showing a change in inbox placement.
Personal inbox coverage
Check Yahoo, Gmail, Outlook, Proton Mail and iCloud accounts to see where your consumer campaigns and notifications land.
Professional inbox coverage
Include Google Workspace and Microsoft 365. Business filtering can produce a different result from a personal account.
Get notified on inbox placement changes
Get inbox placement change alerts in Slack or Microsoft Teams. Keep your team informed when delivery shifts so you can investigate the affected sender or provider.
Three ways to test inbox placement.
Use your real sending service and campaign content. Choose scheduled monitoring, a manual test or the API, with results in the same dashboard.
Schedule regular checks
Connect your sending service, choose your audience and set a schedule. Compare results over time to catch placement changes.
Run a manual test
Create a test, use its tracking code as the subject and send to the supplied seed addresses. Check the result before your next send.
Test through the API
Create tests and retrieve provider results from your own app or workflow. Trigger a check whenever a campaign, template or sender changes.
Same campaign. Different folders.
The useful result is knowing which provider needs your attention.
What one HubSpot test revealed
In the completed run documented in our HubSpot placement guide, the campaign reached all four controlled test accounts. Their folders differed:
- Gmail personal: Promotions.
- Google Workspace: Promotions.
- Outlook personal: Spam.
- Microsoft 365: Focused.
That points the next investigation at the Outlook result. Promotions is a delivered category, and Microsoft 365's result describes a separate business mailbox. One overall percentage would hide those differences.
These are observations from one campaign test, not a prediction for every HubSpot send. The guide includes the completed report and the steps to run your own check.
Turn a result into a useful retest
Open the affected provider result and review the recorded content and domain findings. Correct a specific issue, such as sender authentication or a broken campaign link, then test the revised campaign with a fresh marker and seed list. Keep the sender and provider coverage comparable so you can see what changed. A pending result still needs time; "not received" needs investigation rather than an assumed inbox or spam label.
Evaluate MailSlurp with the email you plan to send
Keep the real campaign and sending service
MailSlurp gives you the test addresses and marker. Send from your normal platform with the campaign's actual sender, template and links. Follow the Mailchimp campaign guide or Klaviyo campaign guide for a practical starting point. Choose the personal and business inbox coverage that reflects your audience.
Try a repeat check before committing to a routine
Run a manual campaign check first. Then connect a supported sending service for scheduled tests, or use the API to trigger checks from your own workflow. Compare completed provider results across runs. When reviewing plans, allow for the number of senders, test frequency and provider coverage your team will use. The automation and reports guide explains recurring testing and report access.
Finish the campaign review in MailSlurp
Placement is one part of send day. Use device previews to inspect the delivered email on phones and desktops, then run Email Audit for links, images and other content issues. Share the findings with the people approving the campaign. Your team can make the placement, layout and content decisions in the same platform before returning to the email provider to send.
Questions about switching from Folderly?
Why choose MailSlurp as a Folderly alternative?
Choose MailSlurp to take a campaign from placement testing through visual and content review. Test the message from your usual email provider, inspect each mailbox outcome, then use device previews and Email Audit before launch. Your team can run checks in the app and use the API when the same checks need to repeat automatically. Explore inbox placement testing.
How does this compare with Folderly Inbox Insights?
Folderly's Inbox Insights documentation describes placement tests using connected mailboxes and templates, including recurring schedules. Evaluate MailSlurp with the actual campaign and sending path you want to check. Compare the included personal and business providers, individual folder results, follow-up diagnostics and the cost of your intended testing schedule. Folderly's recurring-test documentation.
Can I keep HubSpot, Mailchimp or Klaviyo?
Yes. Create a MailSlurp placement test, add its current marker to the campaign and send to the supplied seed addresses through your email platform. Keep those test recipients separate from subscribers. Use the provider guide for the right contact, consent and campaign-send settings. Find your provider's placement guide.
Does an inbox result guarantee the next campaign will avoid spam?
A placement result records what happened in the tested accounts during that run. Your subscribers have different histories and engagement, and providers can change their filtering. Use repeat tests with a consistent sender alongside authentication, list quality and engagement checks to make a better sending decision.
Put your next campaign to the test.
Start free with MailSlurp and see where your email lands.
