The best replacement for hygrometer is hydrometer.

The best alternatives to hygrometer are rated as following:
★★★★★  hydrometer
★★★★  psychrometer
★★  barometer
★  humidistat
  thermometer
  sling psychrometer
  analog

Your alternative for hygrometer is not listed? Suggest!
Speaking about hygrometer, one probably shouldn't forget about thermometer.

Other search terms related to hygrometer and their ratings are:
★★★★★ thermometer
You have in mind a companion for hygrometer and it is not yet here? Propose!



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hygrometer
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