Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop

Performance

Accessibility

Best Practices

SEO

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.32 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

12.32 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

31 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.148

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

2.49 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

12.35 s

Page Load Progression

391 ms

782 ms

1.2 s

1.6 s

2.0 s

2.3 s

2.7 s

3.1 s

Checks

5 PASS 3 REVIEW 5 FIX

Page Weight Budget

Action

13.4 MB transferred, 158 requests

FIX

13.4 MB transferred, 158 requests

Page weighs 16.3 MB (13.4 MB transferred)

Images are 11.9 MB — compress or use modern formats

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Got: 11.9 MB

JavaScript is 1.1 MB — consider code splitting or lazy loading

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Got: 1.1 MB

Fonts are 223 KB — consider subsetting or using system fonts

Subset fonts to include only used characters, or switch to system font stacks.

Got: 223 KB

158 HTTP requests — consider bundling or reducing

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Estimated 2.8 g CO2 per page load

13.4 MB transferred

158 requests

2.8 g CO2 per page load

Images 11.9 MiB 89%

JavaScript 1.1 MiB 9%

Fonts 223.5 KiB 2%

CSS 62.9 KiB 0%

Other 16.7 KiB 0%

HTML 12.4 KiB 0%

Other 12.3 KiB 0%

Other 5.7 KiB 0%

Other 562 B 0%

Other 0 B 0%

0 2.4 MB 4.9 MB

Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

Third-Party Impact

Action

100% third-party, 0 ms blocking

FIX

100% third-party, 0 ms blocking

Third-party code accounts for 100% of page weight (13.4 MiB of 13.4 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

JS Bundles

Action

65 scripts, 508 KB unused

FIX

65 scripts, 508 KB unused

https://www.instructables.com/assets/js_bundles/25...: 143 KB unused (59%)