TestRail offers Free Trial, but QuAck does not.
TestRail is designed for Large Enterprises, Medium Business and Small Business.
QuAck is designed for Individuals, Large Enterprises, Medium Business and Small Business.
The starting price of QuAck begins at $9.95/User/Month, while pricing details for TestRail are unavailable.
Some top alternatives to TestRail includes Jira, ReQtest, Zoho BugTracker, Bug-Track.com, TestCaseLab, Qase, Kualitee, QuAck, Crash Catch and QA touch.
Some top alternatives to QuAck includes TestRail, CloudQA, Testim, TestCaseLab, QATTS, QACoverage, Qase, Kualitee, ZAPTEST and Automaton.