www.bbc.com

The numbers

First visit

0.653 g CO₂e

Return visit

0.016 g CO₂e

Hosting

unknown

LCP

532 ms

CLS

0.005

TTFB

12 ms

At 10,000 views a month this page emits about 59.3 kg CO₂e a year, roughly 243 km in an average petrol car. The estimate assumes 75% new and 25% returning visitors, a measured cache reload ratio of 2%, and world-average grid intensity. How we calculate this

1. Audit third-party servicessave ~0.242 g/visit (2.16 MB)High impact · moderate effort

   20 third-party domains account for 4.32 MB (98% 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.files.bbci.co.uk1.92 MB
   • ichef.bbci.co.uk1.55 MB
   • cdn.privacy-mgmt.com220 kB
   • cdn.tinypass.com140 kB
   • mybbc-analytics.files.bbci.co.uk115 kB
   • cdn.optimizely.com110 kB

   WSG 3.5: Treat third parties the same as first parties
2. Reduce JavaScript payloadsave ~0.057 g/visit (512 kB)High impact · moderate effort

   139 scripts total 2.05 MB on the wire (7.29 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.

   • tinypass.min.js140 kB
   • bundle-default-vendors.2801ec656e2fdff94c17.js126 kB
   • echo-2.6.0-avi.min.js112 kB
   • bbcx_prod.js99 kB
   • Notice.97af9.js95 kB

   WSG 3.2: Minify and remove unused codeWSG 3.3: Modularize bandwidth-heavy components
3. Optimize web fontssave ~0.021 g/visit (185 kB)Medium impact · quick fix

   8 font files total 530 kB.

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

   • BBCReithSerif_W_Rg.woff281 kB
   • BBCReithSerif_W_Md.woff280 kB
   • BBCReithSans_W_Rg.woff267 kB
   • BBCReithSans_W_Rg.woff267 kB
   • BBCReithSans_W_Md.woff266 kB

   WSG 2.11: Use optimized web typography
4. 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
5. Upgrade compression beyond gzipsave ~0.032 g/visit (285 kB)Advisory · quick fix

   1.90 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.

   • bundle-default-vendors.2801ec656e2fdff94c17.js126 kB
   • bbcx_prod.js99 kB
   • Notice.97af9.js95 kB
   • www.bbc.com92 kB
   • bundle-website.611c7498a385ff8dab21.js86 kB

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

   At 4.41 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
7. Remove the entry redirectAdvisory · quick fix

   The address that was scanned goes through 1 redirect before the document is served, ending at https://www.bbc.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://bbc.co.uk/redirects to https://www.bbc.com/

   WSG 4.4: Setup necessary error pages and redirection links
8. Simplify the document structureAdvisory · larger effort

   The page renders 2548 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

• JavaScript2.05 MB · 139 req
• Images1.55 MB · 75 req
• Fonts530 kB · 8 req
• HTML180 kB · 4 req
• Data (fetch)66 kB · 6 req
• Data (XHR)25 kB · 13 req
• CSS6.9 kB · 1 req