BrokenLinkCheck - Free Broken Link Checker / Online Dead Link Checking Tool - find bad hyperlinks
PrepostSEO Guest Posting - Daily Updated (10-30 sites added daily)- Publish Guest Posts at high authority guest posting sites (blogs). All premium websites listed.
Dead Link Checker - Check for broken links on any website
Adsy - Adsy is a guest posting service offering advantages for publisher and buyers. Only quality sites DA40+
LinkChecker - LinkChecker is a free, GPL licensed website validator.
PrePostSEO Domain Authority Checker - DA PA Checker (Domain Authority Checker) is developed to check bulk DA PA with spam score & IP Address for up to 500 URLs at once.