Currency and Number Fields Round When There Are More Than 15 Characters to the Left or Right of the Decimal

Overview

Currency and number fields in Salesforce may round unexpectedly when the field length is set to 16 or more characters to the left or right of the decimal point with 2 decimal places. This rounding can also occur in whole number fields where the numeric value is longer than 15 digits.

Examples of Affected Values

The following examples show how values round when they exceed 15 significant digits:

• 1,222,333,444,555,666.88 becomes 1,222,333,444,555,667
• 1,222,333,444,555,666.84 becomes 1,222,333,444,555,666.80
• 1,222,333,444,555,666.56 becomes 1,222,333,444,555,666.50
• 1,222,333,444,555,666.35 becomes 1,222,333,444,555,666.20
• 1,222,333,444,555,666.12 becomes 1,222,333,444,555,666
• 49.9999999999999972 becomes 50
• 9999999999999999 becomes 10000000000000000

These rounding behaviors occur with currency or number fields configured with 16 or more digits on either side of the decimal, or whole number fields with more than 15 digits.

Why This Happens

JavaScript uses double-precision 64-bit floating-point numbers (IEEE 754 standard), which can only accurately represent integers up to 2^53 (approximately 9 quadrillion, or 9,007,199,254,740,992). Numbers larger than this threshold lose precision when processed in JavaScript.
Since Salesforce's Lightning Experience UI uses JavaScript to render field values, any number exceeding this threshold is subject to rounding when displayed or edited in the browser. This is a JavaScript platform limitation and is not specific to Salesforce — the same rounding occurs in any JavaScript environment, including browser developer consoles.