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@article{195095,
        author = {Prince Gupta and Aaditya Kumar Rai and Rahul and Manvi Gautam and Anurag},
        title = {The Impact of React Server Components (RSC) on Initial Load Times: A Performance Audit Comparing Traditional Client-Side Rendering (CSR) with the RSC Paradigm},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {10},
        pages = {7502-7512},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=195095},
        abstract = {The emergence of React Server Components (RSC) as a stable architectural feature in Next.js 14 and React 18 has opened new possibilities for improving web application performance. Traditional Client-Side Rendering (CSR) requires the browser to download, parse, and execute JavaScript bundles before displaying content — a sequential waterfall that produces poor initial load performance, particularly on constrained networks and low-end devices.
This paper presents a two-stage investigation. In Stage 1, a structured performance audit was conducted using Google Lighthouse 11, Chrome DevTools, and a custom Python measurement script, collecting 300 measurements per variant across three network conditions (Broadband, 4G, 3G) on three application types: an e-commerce product listing, an analytics dashboard, and a blog page. In Stage 2, the authors conducted an independent replication study using Playwright-based automated measurement on locally-served CSR and RSC prototypes, collecting 180 measurements across the same three network conditions to isolate individual performance mechanisms.
The Stage 1 audit results show that RSC implementations reduce First Contentful Paint (FCP) by a mean of 36.8%, Largest Contentful Paint (LCP) by 30.4%, and Total Blocking Time (TBT) by 49.7% compared to equivalent CSR implementations. JavaScript bundle sizes were reduced by an average of 42.3%. Stage 2 replication confirmed that RSC delivers an 82% reduction in JavaScript payload (from 1,315 to 237 characters in the prototype) and demonstrated that the FCP advantage of RSC is network-dependent: on 3G conditions where round-trip latency is highest, RSC FCP was 4.9% faster; under local broadband conditions that eliminate network latency, CSR FCP was marginally faster, isolating the network waterfall as the primary mechanism of RSC improvement. A minor regression in Time to Interactive (TTI) was observed in RSC under 3G (+13.3%) due to the larger pre-rendered HTML payload requiring additional parse time on slow connections.
These findings provide empirical justification for RSC adoption in production applications where network conditions include latency, and contribute a reproducible benchmark methodology with open-source code to the research community.},
        keywords = {React Server Components, Client-Side Rendering, Web Performance, Core Web Vitals, Next.js, First Contentful Paint, JavaScript Bundle Optimisation, Time to Interactive, Playwright, AKTU MCA Research.},
        month = {March},
        }