child's play, easy as/that's

child's play

1. Something that is very easy or simple to perform. Oh please, I've been playing guitar for 20 years—that song is child's play.
2. Something that is insignificant. Those drafts are child's play compared to my latest one—I think I really have a strong argument now.
See also: play
Farlex Dictionary of Idioms.

child's play

something very easy to do. The test was child's play to those who took good notes. Finding the right street was child's play with a map.
See also: play
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

child's play

Something easily done, a trivial matter. For example, Finding the answer was child's play for Robert, or The fight we had was child's play compared to the one I had with my mother! Originating in the early 1300s as child's game, the idiom was already used in its present form by Chaucer in The Merchant's Tale: "It is no child's play to take a wife."
See also: play
The American Heritage® Dictionary of Idioms by Christine Ammer.

child's play

COMMON If something is child's play, it is very easy to do, especially compared with something else that is very difficult. He thought the work would be child's play. The problem in Western Europe was described by one EU energy expert as child's play compared to that in Eastern Europe.
See also: play
Collins COBUILD Idioms Dictionary, 3rd ed.

child's play

a task which is very easily accomplished.
See also: play
Farlex Partner Idioms Dictionary

ˈchild’s play

a very easy job or task: Mending the lamp was child’s play for an experienced electrician like him. OPPOSITE: a tall order
See also: play
Farlex Partner Idioms Dictionary

child's play, easy as/that's

Extremely simple, easily accomplished. The earliest use of this simile appears in Chaucer’s The Merchant’s Tale: “I warne yow wel, it is no childes pley to take a wyf with-outen avysement.” It was probably a cliché by the time Thomas Carlyle wrote, “The craftsman finds it no child’splay” (Chartism, 1839).
See also: easy
The Dictionary of Clichés by Christine Ammer
See also:
  • a horse of another
  • a horse of another color
  • a horse of another colour
  • (you) wanna make something of it?
  • a crack at (someone or something)
  • (you've) got to get up pretty early in the morning to (do something)
  • a/the feel of (something)
  • (I) wouldn't (do something) if I were you
  • a thing of the past
  • a straw will show which way the wind blows