Google Sheets Add-ons

MSOfficeAddin specializes in custom Google Sheets add-on development, transforming standard spreadsheets into sophisticated data processing engines. We build powerful Google Sheets add-ons using Apps Script that automate complex calculations, integrate with external REST APIs, and extend core spreadsheet functionality with custom menus, interactive sidebars, and specialized dialogs. Our developers create custom functions that perform tasks beyond standard formulas, such as real-time currency conversion, automated data cleaning, or pulling live lead data from your CRM. We focus on bridge-building, connecting your Google Sheets environment to SQL databases, BigQuery, and third-party SaaS platforms via secure OAuth 2.0 flows. Whether you need an automated dashboard for financial reporting, a bulk email tool that pulls data directly from rows, or a custom internal tool for inventory management, our team delivers high-performance, scalable solutions that speed up your data work and cut out manual entry errors.

A performance marketing agency ran month-end client reporting out of nine template spreadsheets, each fed by CSV downloads from three ad platforms. Two account managers lost most of a week to it, and clients got numbers that were already days old. We built a Sheets sidebar that signs in to each platform's API once, pulls spend and conversion data straight into the templates on a schedule, and flags rows where spend jumped past a client's threshold. The same data now flows into a summary tab their finance lead reads on the first of the month. Reporting week became reporting morning. The account managers' favourite feature was not the automation but the audit note the script writes into each tab recording when data was fetched and from where.

A custom Sheets build pays off when spreadsheets are the team's real working surface and data arrives from systems with APIs. If your process would be better served by a proper database or BI tool, we say that in the scoping call. And when the output of the spreadsheet is a formatted document rather than analysis, pairing Sheets with a Docs automation build usually completes the workflow.