[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-25 UTC."],[],[],null,["# ln\n\nThe `ln` function can be used in [custom filters](/looker/docs/2512/filtering-and-limiting#custom-filters) and [table calculations](/looker/docs/2512/table-calculations) to get the natural logarithm of a value.\n\nSyntax\n------\n\n**`ln(value)`**\n\nThe `ln` function takes the logarithm of a `value` to the base of the mathematical constant *e*.\n\nExamples\n--------\n\nThe `ln` function can be used to model exponential growth linearly by taking `ln` of the dependent variable. For example: \n\n ln(order_items.growth_rate)\n\nThings to know\n--------------\n\n`ln` can be used to give you the time needed to reach a certain level of growth.\nFor instance, modeling growth exponentially as:\n\n*growth = e^time^*\n\n*time* can be determined using `ln` as follows: \n\n ln(growth)"]]
