Sin appears in the Bible 415 times. 308 times in the Old Testament (OT) and 107 times in the New Testament (NT). [Sin is also a geographical place referred to 6 times, all in the OT.] variations of "sin" are: Sinful - 8 times, 3 in the OT and 5 in the NT. Sinned - 117 times, 101 in the OT and 16 in the NT. Sinner - 21 times, 9 in the OT and 12 in the NT. Sinners - 47 times, 16 in the OT and 31 in the NT. Sinnest - once, in the OT. Sinneth - 22 times, 15 in the OT and 7 in the NT. Sinning - twice, in the OT. Sins - 170 times, 84 in the OT and 86 in the NT. Source: Strong's Exhaustive Concordance.

Occurences of the word sin in the bible.
 
In the Protestant version:
Old Testament  297 times
New Testament 90 times 
 
In the Catholic version:
Old Testament 372 times
New Testament 98 times
 

In the New International Version:

Sin= 473
Sins= 292
Sinful= 54
Sinfulness= 1
Sin's= 1
Sinned= 89
Sinners= 20
Sinner's= 1
Sinning= 20

1John 3:4 Everyone who sins breaks the law; in fact, sin is lawlessness.

Proverb 16:6 Through love and faithfulness sin is atoned for; through the fear of the LORD a man avoids evil.

Romans 6:23 For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord.

In the King James Version: 561
Sin 448x,
Sinneth 22x,
Sinning 2x,
Sinners 48x,
Sinner 41x
= 561x

1016 sin  (King James Version)

The word sin occur 389 times in the Bible. Genesis 4:7; Exodus 17:1