www.apple.com/mac

The numbers

First visit

0.798 g CO₂e

Return visit

0.562 g CO₂e

Hosting

unknown

LCP

1.09 s

CLS

0.087

TTFB

15 ms

At 10,000 views a month this page emits about 88.7 kg CO₂e a year, roughly 363 km in an average petrol car. The estimate assumes 75% new and 25% returning visitors, a measured cache reload ratio of 70%, and world-average grid intensity. How we calculate this

1. Convert and compress imagessave ~0.194 g/visit (1.42 MB)High impact · quick fix

   26 images (188 kB) ship in legacy formats (JPEG/PNG/GIF); 3 images exceed 300 kB apiece.

   Serve AVIF (or WebP) with responsive srcset sizes, and re-compress oversized files. AVIF typically halves JPEG weight at the same visual quality.

   • mac1.04 MB
   • mac1.04 MB
   • mac1.04 MB
   • mba_13_15_e733a3435.jpg27 kB
   • studio_display_xdr_fef4b71f1.jpg24 kB

   WSG 2.9: Optimize media to reduce resource use
2. Reduce JavaScript payloadsave ~0.027 g/visit (195 kB)High impact · moderate effort

   44 scripts total 779 kB on the wire (2.14 MB decoded). Bundles this size usually carry a lot of unused code.

   Split bundles per route, tree-shake dependencies, and audit with a bundle analyzer or coverage profile. A 25% cut is a conservative target for bundles this size.

   • globalheader.umd.js165 kB
   • ac-analytics.js104 kB
   • 4011.6f26d45a9009e19d.js85 kB
   • framework-33b5afb7a08c1576.js59 kB
   • localeswitcher.built.js57 kB

   WSG 3.2: Minify and remove unused codeWSG 3.3: Modularize bandwidth-heavy components
3. Optimize web fontssave ~0.045 g/visit (326 kB)Medium impact · quick fix

   7 font files total 933 kB.

   Subset fonts to used glyphs, prefer one variable font over multiple weights, serve WOFF2 only, and consider system fonts for UI text.

   • sf-pro-text_semibold.woff2235 kB
   • sf-pro-text_light.woff2226 kB
   • sf-pro-text_regular.woff2222 kB
   • sf-pro-display_semibold.woff2130 kB
   • sf-pro-text_regular-italic.woff289 kB

   WSG 2.11: Use optimized web typography
4. Enable text compressionsave ~0.020 g/visit (148 kB)Medium impact · quick fix

   2 text resources (211 kB) are served without gzip/Brotli.

   Enable Brotli (or at least gzip) on the server or CDN for HTML, CSS, JavaScript, JSON and SVG. Typical reduction is ~70%.

   • globalheader.umd.js165 kB
   • flyouts46 kB

   WSG 4.3: Reduce data transfer with compression
5. Verify your hosting energyMedium impact · moderate effort

   This host has not published renewable energy evidence with the Green Web Foundation, so its energy source is unknown.

   Choose a provider listed in the Green Web Directory, or ask your current provider to publish evidence (and a carbon.txt). This cuts the data-center share of every single page view.

   WSG 4.1: Use sustainable hosting
6. Stop downloading the same asset twicesave ~0.180 g/visit (1.31 MB)Advisory · quick fix

   1 asset was fetched more than once in a single page load (3.11 MB of repeated transfer).

   Usually a script injected twice or cache-busting query strings that differ per reference. Load each asset once and let the HTTP cache do its job.

   • mac4 downloads · 3.30 MB

   WSG 3.2: Minify and remove unused code
7. Upgrade compression beyond gzipsave ~0.083 g/visit (606 kB)Advisory · quick fix

   4.04 MB of text ships gzip-compressed; Brotli or Zstandard would cut roughly another 15-20%, and browsers without them fall back to gzip automatically.

   Serve precompressed Brotli for static text assets (highest level, compressed at build time) and enable Brotli or zstd for dynamic responses; keep gzip only as the fallback.

   • mac1.04 MB
   • mac1.04 MB
   • mac1.04 MB
   • mac185 kB
   • ac-analytics.js104 kB

   WSG 4.3: Reduce data transfer with compression
8. Set a page-weight budgetAdvisory · moderate effort

   At 5.38 MB per view this page rates F. The findings above list where the weight is.

   Agree a transfer budget (e.g. under 975 kB reaches a B), enforce it in CI, and re-scan after each change to hold the line.

   WSG 3.1: Set goals based on performance and energy impact
9. Simplify the document structureAdvisory · larger effort

   The page renders 3373 DOM elements, above the 1,500 guideline. Large trees cost memory and CPU on every visitor's device.

   Flatten wrapper markup, render long lists virtually or paginate, and prefer semantic elements over nested divs.

   WSG 3.6: Ensure code follows good semantic practices

Where the bytes are

• Images3.30 MB · 31 req
• Fonts933 kB · 7 req
• JavaScript779 kB · 44 req
• HTML185 kB · 1 req
• CSS130 kB · 32 req
• Data (fetch)47 kB · 2 req
• Data (XHR)4.9 kB · 3 req