| Abstract: New all-sky surveys are increasingly becoming available with higher sensitivity, resolution, and fidelity (sensitivity to both compact and diffuse emission). At the same time, the scientific exploitation of these open datasets is no longer limited to professional astronomers; trained citizen scientists working outside formal research institutions are also making substantive contributions. To facilitate the analysis of both legacy and newly available radio interferometric data by professional and amateur astronomers alike, we have developed a simple online tool that generates quick-look spectral index maps from any pair of FITS images (https://sites.google.com/view/radiospectralindex/home). The tool is subject to natural limitations arising from the UV-coverage of the input images and a maximum file size of 100 MB. Uploaded FITS files are not stored, ensuring that users can analyse data without compromising the privacy of newly identified radio sources. The service is free to use and is hosted on Google Sites, offering a lightweight interface with backend computations performed on a Streamlit server. The backend utilises established Python libraries such as radio_beam and reproject to implement a rigorous common-resolution workflow. Worst-case beam parameters are automatically derived from FITS metadata of major surveys (e.g. LoTSS, LoLSS, NVSS, TGSS, FIRST, and RACS), and a flux-conserving circular convolution kernel is generated to homogenise angular resolution and eliminate directional bias. Unlike static spectral-index servers, the pipeline allows interactive adjustment of noise thresholds (e.g. 3σ, 5σ). Quick-look images are displayed directly in the browser, and the final spectral index maps can be downloaded in FITS format for further analysis. While the tool is openly available to all users, it is currently being tested and refined through active use by trained citizen scientists from RAD@home India, who are working beyond preliminary RGB–contour-based analyses (https://www.radathomeindia.org/rgbmaker).
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