The best alternatives to Clocker are Dato, ClockDock, and EveryTimeZone. If these 3 options don't work for you, we've listed a few more alternatives below.
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AssemblyAI— Speech-to-Text API with superhuman accuracy
Dato is a replacement for the system menu bar clock. By default, it looks exactly the same, but when you click it, you get a small calendar, calendar events, the current time in various time zones, and more.
Easily find the exact time difference with the visual Time Zone Converter. Find meeting times for your contacts, locations and places around the world. Never warp your brain with time zone math again.
SubClock is an improved clock menu app for mac osx. View your time in sub seconds. Minimal yet fully customizable. Change how you want to display the time.