How much do CDN and image compression strategies improve site speed?

Short answer: The gain is not a fixed number; it depends on your current infrastructure, image weight, and where your traffic comes from. The honest approach is to measure a baseline first and report the improvement against it.

The mechanism is clear: a CDN serves static assets from an edge close to the user, cutting latency, while modern formats (WebP, AVIF) and correct sizing lighten the largest content element. Together they mostly move LCP; Google's published threshold for LCP is 2.5 seconds.

A measurable improvement loop

• Baseline: record current LCP, TTFB, and image weight with CrUX data and Lighthouse.
• Implementation: CDN cache rules, an image CDN or build-time compression, correct sizes via srcset, fetchpriority on the critical image.
• Validation: watch the 75th percentile LCP across 28 days of field data instead of trusting a single lab run.

TYS Digital Performance does not promise invented percentages here: we take your site's own baseline, ship the change, and report the measured difference from field data.