www.facebook.com

The numbers

First visit

0.294 g CO₂e

Return visit

0.040 g CO₂e

Hosting

unknown

LCP

900 ms

CLS

0

TTFB

143 ms

At 10,000 views a month this page emits about 27.6 kg CO₂e a year, roughly 113 km in an average petrol car. The estimate assumes 75% new and 25% returning visitors, a measured cache reload ratio of 14%, and world-average grid intensity. How we calculate this

1. Audit third-party servicessave ~0.110 g/visit (949 kB)High impact · moderate effort

   3 third-party domains account for 1.90 MB (96% of the page).

   Remove services that no longer earn their place; load the rest on interaction (facades for embeds, delayed consent-gated tags). Each third party is also a privacy and performance dependency.

   • static.xx.fbcdn.net1.89 MB
   • www.instagram.com4.1 kB
   • 0 B

   WSG 3.5: Treat third parties the same as first parties
2. Reduce JavaScript payloadsave ~0.035 g/visit (299 kB)High impact · moderate effort

   22 scripts total 1.20 MB on the wire (4.80 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.

   • nSKhwb6dZVZ.js225 kB
   • eXMyMi0dTNv2qgvuYi1BOD8k0my6Pj0O8v_kkAv_-wGQi…215 kB
   • SkBt9mDbIgj.js154 kB
   • 3dkqfsNscuw.js108 kB
   • qiJ4HZ44mWpuWPBotkU1vk82Yz_4vfOJLGAsRBnpddaml…96 kB

   WSG 3.2: Minify and remove unused codeWSG 3.3: Modularize bandwidth-heavy components
3. Serve images at the size they displaysave ~0.011 g/visit (97 kB)Medium impact · quick fix

   1 image is encoded at more than twice the pixels the layout shows, even accounting for this viewport's pixel density.

   Generate multiple sizes and let the browser pick with srcset/sizes; a 4000px original behind a 400px slot spends bandwidth no screen displays.

   • HpEiFYDux5j.webp194 kB

   WSG 2.9: Optimize media to reduce resource use
4. Fix caching for returning visitorssave ~0.0071 g/visit (48 kB)Medium impact · quick fix

   On a repeat visit 192 kB of static assets were re-downloaded instead of coming from cache.

   Serve static assets with Cache-Control: public, max-age=31536000, immutable and versioned filenames so returning visitors download almost nothing.

   • U45qBJmWVHU.webpCache-Control: public,max-age=31536000,immutable · 182 kB
   • V15tj8h63LNXV_vKBEegn763T-omr2qwML2OjEpNOBjYR…Cache-Control: public,max-age=31536000,immutable · 11 kB

   WSG 4.2: Optimize caching and support offline access
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.

   • carbon.txtNo carbon.txt found at the site root; publishing one is the lightest first step.

   WSG 4.1: Use sustainable hosting
6. Optimize web fontssave ~0.0087 g/visit (75 kB)Advisory · quick fix

   2 font files total 213 kB.

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

   • -pkMfchyeAZ.woff2183 kB
   • 9AJbVCy4-G1.woff230 kB

   WSG 2.11: Use optimized web typography
7. Set a page-weight budgetAdvisory · moderate effort

   At 1.98 MB per view this page rates D. 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
8. Remove the entry redirectAdvisory · quick fix

   The address that was scanned goes through 1 redirect before the document is served, ending at https://www.facebook.com/. Every hop is a full round trip on a connection that has not warmed up yet.

   Point links, sitemaps and canonical tags at the final address, and make the host redirect in one hop rather than chaining http to https to www.

   • https://facebook.com/redirects to https://www.facebook.com/

   WSG 4.4: Setup necessary error pages and redirection links

Where the bytes are

• JavaScript1.20 MB · 22 req
• CSS287 kB · 2 req
• Fonts213 kB · 2 req
• Images197 kB · 2 req
• HTML82 kB · 1 req
• Data (XHR)4.4 kB · 2 req
• Other1.5 kB · 1 req