<p>Indoor air quality is crucial for human health and well-being, directly influencing respiratory function and overall comfort. Poor indoor air quality can lead to various health issues, including respiratory problems, allergies, and the exacerbation of pre-existing conditions, emphasizing the importance of maintaining a healthy indoor environment. This study aims to examine the synergistic impact of filter integration and botanical solution in enhancing air quality. A botanical indoor air biofilter (BIAB) rig that utilizes the low-cost Internet of things approach was developed. The air quality parameters are particulate matter 2.5 (PM2.5) and particulate matter 10 (PM10), volatile organic compounds (VOCs), carbon dioxide (CO₂), air temperature, and relative humidity (RH). The smart sensors operated on RS485 Modbus protocol were integrated into the BIAB to monitor the real-time fluctuations of air quality parameters. A total of 5 combinations of parametric studies are tested, ranging from the usage of botanical plants, carbon filters, coconut husk, and granular activated carbon (GAC). These combinations were designed to assess the impact of different filtration configurations on the overall effectiveness of the system in reducing air pollutants. Results show that Case 3 (integrating botanical plants and a primary carbon filter) has the highest average reduction rate on PM2.5 with 5.36&#xa0;µg/m³ per minute and VOCs with 4.13&#xa0;μg/m³ per minute, respectively. However, Case 5 (integrating additional GAC) contributes to the highest reduction of PM10 concentration, with an average reduction rate of 5.23&#xa0;ppm per minute.</p> Graphical abstract <p>Overview of Optimizing Indoor Air Quality with Filter Integration, Botanical Solutions, and IoT Smart Sensors in Indoor Environments</p> <p></p>