Difference between toFixed() and toPrecision()?

javascript rounding precision
Jessica picture Jessica · Jul 26, 2010 · Viewed 55.1k times · Source

I'm new to JavaScript and just discovered toFixed() and toPrecision() to round numbers. However, I can't figure out what the difference between the two is.

What is the difference between number.toFixed() and number.toPrecision()?

Answer

Pops picture Pops · Jul 26, 2010

toFixed(n) provides n length after the decimal point; toPrecision(x) provides x total length.

Ref at w3schools: toFixed and toPrecision

EDIT:
I learned a while back that w3schools isn't exactly the best source, but I forgot about this answer until I saw kzh's, uh, "enthusiastic" comment. Here are additional refs from Mozilla Doc Center for toFixed() and for toPrecision(). Fortunately for all of us, MDC and w3schools agree with each other in this case.

For completeness, I should mention that toFixed() is equivalent to toFixed(0) and toPrecision() just returns the original number with no formatting.

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