Site speed is a revenue lever wearing a technical costume: slower pages convert measurably worse, rank worse, and burn ad spend on visitors who leave before paint. Most speed advice lists forty tips; the needle moves on about six. Here they are, ordered by impact, calibrated for Indian mobile reality — mid-range Android on inconsistent 4G.
The metrics that count
Google's Core Web Vitals: LCP (largest contentful paint — when the main content shows; target <2.5s), INP (interaction to next paint — how fast taps respond; target <200ms), CLS (layout shift — does the page jump; target <0.1). Measure on PageSpeed Insights with mobile numbers — desktop scores flatter everyone.
The six things that move it
1. Images (usually 60% of the problem). Modern formats (WebP/AVIF), sized to their containers, lazy-loaded below the fold, eagerly loaded for the LCP hero. One unoptimized hero image routinely costs two seconds.
2. JavaScript discipline. Every marketing tag, chat widget, and carousel library ships to that mid-range Android and executes. Audit ruthlessly; load non-critical scripts after interaction; delete the three plugins nobody remembers adding. This is where WordPress sites lose to engineered ones — but WordPress can be disciplined too.
3. Server response / rendering strategy. Static or edge-rendered pages start fast everywhere; India-region hosting or a CDN stops shipping every request to Frankfurt and back.
4. Font handling. Two families max, font-display: swap, preloaded — or system fonts and zero cost. Invisible text waiting on a font download is self-inflicted LCP damage.
5. Layout stability. Reserved space for images/ads/embeds. CLS is UX rage quantified — the button that jumps as you tap it.
6. Third-party audit, quarterly. Tags accrete like barnacles. The maintenance discipline includes scraping the hull.
What it costs and returns
A proper speed pass on an existing site runs ₹40k–1.5L depending on how deep the archaeology goes; new builds should simply ship fast by architecture. Returns: conversion lifts of 5–20% on previously-slow sites are routine, plus ranking and ad-quality-score effects. Baseline before, measure after — the usual honesty.
Send us your URL and we will tell you which of the six is eating your revenue — free look, honest answer.
Frequently asked questions
What actually makes websites slow?
In order of typical impact: unoptimized images (often 60% of the problem), JavaScript bloat from tags and widgets, slow server response without CDN/edge rendering, font-loading mistakes, layout shift from unreserved space, and accreted third-party scripts.
What are Core Web Vitals targets?
LCP under 2.5 seconds (main content visible), INP under 200ms (taps respond), CLS under 0.1 (no layout jumping) — measured on mobile via PageSpeed Insights, since desktop scores flatter everyone and Indian traffic is mid-range Android on 4G.
How much does website speed optimization cost?
A proper optimization pass on an existing site runs ₹40,000–1.5 lakh in India depending on depth. New builds should ship fast by architecture instead — retrofitting speed always costs more than designing for it.
Does site speed really affect revenue?
Measurably: conversion lifts of 5–20% on previously slow sites are routine, plus ranking improvements and better ad quality scores. Slow pages burn ad spend on visitors who leave before the page paints.