AbuseBox is a self-hosted monitor for the mail servers you operate, checking your IPs and domains against 24 DNS blacklists on a schedule and alerting you when a listing appears, disappears, or is about to matter. A listing is never just a red flag. AbuseBox decodes each list's return codes into a plain meaning and a severity, links the removal page, and folds the result into a risk score out of 100 for every asset, with each factor and its contribution shown. Before any verdict is trusted, the list itself is tested against its RFC test addresses, so a resolver being refused reads as No answer rather than clean. The same asset page grades SPF, DKIM, and DMARC from A to F, parses DMARC aggregate reports, and tracks certificate validity, domain expiry, DNS records, WHOIS details, and server reachability with response times. Assets arrive one at a time, in bulk lists of up to 300, or as an entire subnet, each with its own owner, check selection, and interval. The activity log records every change, history charts show the trend, and email, Slack, Discord, or webhook alerts carry the news. A public quick-check page answers one-off lookups without an account, and the REST API covers the rest. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.