The word(s) "sin" appears 521 time(s) in 480 verse(s) in Quran in Mohsin Khan translation.

(471) But they (disbelievers, sinners) had not been sent as watchers over them (the believers).

(472) And by the Witnessing day (i.e. Friday), and by the Witnessed day [i.e. the day of 'Arafat (Hajj) the ninth of Dhul-Hijjah];

(473) There is indeed in them (the above oaths) sufficient proofs for men of understanding (and that, they should avoid all kinds of sins and disbeliefs)!

(474) "Come back to your Lord well-pleased (yourself) and well-pleasing (unto Him)!

(475) And you are free (from sin, and to punish the enemies of Islam on the Day of the conquest) in this city (Makkah).

(476) Thamud (people) denied (their Prophet) through their transgression (by rejecting the true Faith of Islamic Monotheism, and by following polytheism, and by committing every kind of sin).

(477) Then they denied him and they killed it. So their Lord destroyed them because of their sin, and made them equal in destruction (i.e. all grades of people, rich and poor, strong and weak, etc.)!

(478) By Mount sinai.

(479) A lying, sinful forelock!

(480) Except those who believe (in Islamic Monotheism) and do righteous good deeds, and recommend one another to the truth [i.e. order one another to perform all kinds of good deeds (Al-Ma'ruf) which Allah has ordained, and abstain from all kinds of sins and evil deeds (Al-Munkar which Allah has forbidden], and recommend one another to patience (for the sufferings, harms, and injuries which one may encounter in Allah's Cause during preaching His religion of Islamic Monotheism or Jihad).