--- title: Buy | Knowledge base (Legacy) description: This module optimizes the buy quantities to match the future season sales without waste or reducing the end of season quantities. --- [Skip to content](https://help.nextail.co/en/legacy/buy#main-content) - [English](https://help.nextail.co/en/legacy/buy) - [Español](https://help.nextail.co/es/legacy/compra) - [Français](https://help.nextail.co/fr/legacy/achat) - [Italiano](https://help.nextail.co/it/legacy/acquisto) - [Русский](https://help.nextail.co/ru/legacy/покупка) English Show submenu for translations ![Nextail-logo-rojo (5).png\]](https://help.nextail.co/hs-fs/hubfs/Emails/Nextail-logo-rojo%20(5).png?height=31&name=Nextail-logo-rojo%20(5).png) Open main navigation Close main navigation - - [English](https://help.nextail.co/en/legacy/buy) - [Español](https://help.nextail.co/es/legacy/compra) - [Français](https://help.nextail.co/fr/legacy/achat) - [Italiano](https://help.nextail.co/it/legacy/acquisto) - [Русский](https://help.nextail.co/ru/legacy/покупка) English Show submenu for translations - [Visit nextail.co](https://nextail.co/) [Visit nextail.co](https://nextail.co/) How can we help you? - There are no suggestions because the search field is empty. 1. [Knowledge base (Legacy)](https://help.nextail.co/en/legacy) 2. [Buy](https://help.nextail.co/en/legacy/buy) # Buy This module optimizes the buy quantities to match the future season sales without waste or reducing the end of season quantities. ## Frequently asked questions - [What is the added value of showing the ROS to the customer? Can’t we just give them the final quantity? What is the utility of the ROS, just informative?](https://help.nextail.co/en/legacy/what-is-the-added-value-of-showing-the-ros-to-the-customer-cant-we-just-give-them-the-final-quantity-what-is-the-utility-of-the-ros-just-informative) - [How does Nextail do ROS calculation?](https://help.nextail.co/en/legacy/how-does-nextail-do-ros-calculation) - [Why is an average made when we talk about calculations at family/subfamily?](https://help.nextail.co/en/legacy/why-is-an-average-made-when-we-talk-about-calculations-at-family/subfamily-why-isnt-it-calculated-at-the-most-granular-level-first-subfamily-and-if-there-i-1698731365824) - [When taking the reference weeks to calculate, where are these weeks coming from?](https://help.nextail.co/en/legacy/when-taking-the-reference-weeks-to-calculate-where-are-these-weeks-coming-from-do-we-take-the-reference-weeks-from-the-selling-perimeter-we-select-or-from-1698731404444) - [How does Nextail build seasonality?](https://help.nextail.co/en/legacy/how-does-nextail-build-seasonality-1) ## Articles - [Performance index](https://help.nextail.co/en/legacy/performance-index) - [Parameters impacting the demand forecast](https://help.nextail.co/en/legacy/parameters-impacting-the-demand-forecast) - [Buy: Forecast](https://help.nextail.co/en/legacy/buy-forecast) - [Order Scheduling](https://help.nextail.co/en/legacy/order-scheduling) ## User Guides - [Buy User Guide: Step by step](https://help.nextail.co/en/legacy/buy-user-guide-step-by-step) - [Video Library](https://help.nextail.co/en/legacy/video-library) - [First Allocation](https://help.nextail.co/en/legacy/first-allocation#main-content) - [Frequently asked questions](https://help.nextail.co/en/legacy/first-allocation#frequently-asked-questions) - [User guides](https://help.nextail.co/en/legacy/first-allocation#user-guides) - [Articles](https://help.nextail.co/en/legacy/first-allocation#articles) - [Replenishment](https://help.nextail.co/en/legacy/replenishment#main-content) - [Frequently asked questions](https://help.nextail.co/en/legacy/replenishment#frequently-asked-questions) - [Articles](https://help.nextail.co/en/legacy/replenishment#articles) - [User guides](https://help.nextail.co/en/legacy/replenishment#user-guides) - [Store Transfers](https://help.nextail.co/en/legacy/store-transfers#main-content) - [Frequently asked questions](https://help.nextail.co/en/legacy/store-transfers#frequently-asked-questions) - [User guides](https://help.nextail.co/en/legacy/store-transfers#user-guides) - [Articles](https://help.nextail.co/en/legacy/store-transfers#articles) - [Buy](https://help.nextail.co/en/legacy/buy#main-content) - [Frequently asked questions](https://help.nextail.co/en/legacy/buy#frequently-asked-questions) - [Articles](https://help.nextail.co/en/legacy/buy#articles) - [User Guides](https://help.nextail.co/en/legacy/buy#user-guides) - [Reorder](https://help.nextail.co/en/legacy/reorder#main-content) - [User Guide](https://help.nextail.co/en/legacy/reorder#user-guide) - [Articles](https://help.nextail.co/en/legacy/reorder#articles) - [Frequently Asked Questions](https://help.nextail.co/en/legacy/reorder#frequently-asked-questions) - [Mobile App](https://help.nextail.co/en/legacy/mobile-app#main-content) - [Articles](https://help.nextail.co/en/legacy/mobile-app#articles) - [Frequently asked questions](https://help.nextail.co/en/legacy/mobile-app#frequently-asked-questions) - [User guides](https://help.nextail.co/en/legacy/mobile-app#user-guides) - [Business Intelligence](https://help.nextail.co/en/legacy/business-intelligence#main-content) - [Articles](https://help.nextail.co/en/legacy/business-intelligence#articles) - [Frequently asked questions](https://help.nextail.co/en/legacy/business-intelligence#frequently-asked-questions) - [User Guides](https://help.nextail.co/en/legacy/business-intelligence#user-guides) - [Nextail Optimization Logic](https://help.nextail.co/en/legacy/nextail-optimization-logic#main-content) - [Frequently asked questions](https://help.nextail.co/en/legacy/nextail-optimization-logic#frequently-asked-questions) - [Account Troubleshooting](https://help.nextail.co/en/legacy/account-troubleshooting) - [Glossary of terms](https://help.nextail.co/en/legacy/glossary-of-terms) [![Nextail Logo](https://help.nextail.co/hs-fs/hubfs/Nextail-logo-red.png?width=140&height=33&name=Nextail-logo-red.png "Nextail Logo")](https://nextail.co/) Nextail knowlede base Copyright © 2026, Nextail Labs SLU