GlockApps vs Mail-Tester

GlockApps helps marketers and businesses check email deliverability and investigate placement problems before sending campaigns. Inbox Insight shows whether test messages reach inboxes, spam folders, or subfolders at different providers, and checks them against SpamAssassin, Barracuda, Microsoft Exchange Online Protection, Proofpoint, and a Google filter. Reputation tools check IPs and domains against blocklists and report sender scores and placement by IP. Content analysis covers message size, images, and links, with an HTML compatibility checker. DMARC Analytics collects reports, tracks sending sources, and retains reports for a year. Uptime Monitor checks IPs, SPF, DKIM, DMARC, HTTP, TLS, and TCP, with checks configurable as often as every minute. The API supports automated testing, result retrieval, and client management by projects and folders on all plans, including free. GlockApps runs on the web and through an API. Its free plan includes two spam test credits; paid plans start at $59 a month, billed annually at $708.

Mail-Tester checks an email, its mail server, and sending IP, then gives a spam score and reports configuration findings. To run a test, send a message to an address generated by the service and open the result page. Checks include blocklists, SpamAssassin, SPF, DKIM, Sender-ID, DMARC, links, and pictures. The free plan allows three tests within a rolling 24-hour period. A test counts after a new message is sent, the result page is requested, and the result is returned successfully; reopening that result does not use another test. Free results remain available for 7 days. With an account using its own prefix, results remain available for 30 days. Accounts also provide white-labeling, result-page CSS customization, statistics, a 30-day test listing, and pages without ads. Paid plans include an iframe and JSON API for integration; API output can include message details, authentication checks, body analysis, blacklist results, and broken links. One-time test bundles cost $5 as a one-time purchase to $250, paid once; monthly plans cost $10 a month to $250 a month. Passing does not guarantee inbox placement.