judging by

judging by (something)

Based on something; taking into account and considering something. Judging by his expression, I reckon the boss was as surprised as the rest of us by the news. It looks like the previous tenants didn't even know there was a lawnmower here, judging by the state of the front yard.
See also: by, judge
Farlex Dictionary of Idioms.

judging by something

 and judging from something
to make a decision or judgment based on something. Judging by the amount of food eaten, everyone must have been very hungry. Judging from the mess that's left, the party must have been a good one.
See also: by, judge
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • all for the best
  • a/the feel of (something)
  • (I) wouldn't (do something) if I were you
  • a straw will show which way the wind blows
  • a crack at (someone or something)
  • all right
  • (you) wanna make something of it?
  • a thing of the past
  • a slew of (something)
  • a bird in the hand
References in periodicals archive
Swanson's study confirms the trend toward judging by an increasingly younger group of educators.
The case for using nontraditional judges in forensic contests