Ash-Shu'ara' - 26:181

أَوْفُوا الْكَيْلَ وَلَا تَكُونُوا مِنَ الْمُخْسِرِينَ
[26:181]
Give a full measure and be not of those who diminish;
"Give just measure, and cause no loss (to others by fraud).
Give full measure, and be not of those who give less (than the due).