bogazici.edu.tr

The numbers

First visit

2.04 g CO₂e

Return visit

0.017 g CO₂e

Hosting

unknown

LCP

7.95 s

CLS

0.012

TTFB

42 ms

At 10,000 views a month this page emits about 183.8 kg CO₂e a year, roughly 753 km in an average petrol car. The estimate assumes 75% new and 25% returning visitors, a measured cache reload ratio of 1%, and world-average grid intensity. How we calculate this

1. Convert and compress imagessave ~0.589 g/visit (5.29 MB)High impact · quick fix

   53 images (11.74 MB) ship in legacy formats (JPEG/PNG/GIF).

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

   • 8012-uluslararasi-anlasmalar-20260615-112651_…1.39 MB
   • 774-turkiyenin-en-koklu-20260803-133915_300x2…1.02 MB
   • 135-guvenli-kampusler-20250704-110940_600x400…907 kB
   • 310-yuksekokullar-20250514-221333_600x400.jpg531 kB
   • 104-giden-ogrenciler-20250514-221318_600x400.jpg510 kB

   WSG 2.9: Optimize media to reduce resource use
2. Serve images at the size they displaysave ~0.239 g/visit (2.14 MB)High impact · quick fix

   20 images are 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.

   • 310-yuksekokullar-20250514-221333_600x400.jpg531 kB
   • 87-surekli-egitim-20250415-140311_600x400.png505 kB
   • 87-surekli-egitim-20250415-140311_600x400.png505 kB
   • 16-akademik-20250514-221203_600x400.jpg438 kB
   • 16-akademik-20250514-221203_600x400.jpg438 kB

   WSG 2.9: Optimize media to reduce resource use
3. Enable text compressionsave ~0.099 g/visit (886 kB)High impact · quick fix

   11 text resources (1.27 MB) 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%.

   • main.min.css505 kB
   • bundle.js232 kB
   • swiper-bundle.min.js154 kB
   • all.min.css105 kB
   • jquery.min.js88 kB

   WSG 4.3: Reduce data transfer with compression
4. Lazy-load below-the-fold mediasave ~0.032 g/visit (283 kB)High impact · quick fix

   11 below-the-fold images/iframes (566 kB) download immediately for every visitor.

   Add loading="lazy" to below-fold img and iframe elements (and keep it off the LCP image). Browsers then fetch them only when scrolling approaches.

   • 5-20250124-010805_161x85.jpg361 kB
   • 1-bogazici-universitesi-weblogo-1-20250117000…80 kB
   • 6-getem-20250502-173138_90x60.png26 kB
   • 9-arastirma-20250502-173321_90x60.png24 kB
   • 1-bogazicinde-bilim-20250502-173206_90x60.png22 kB

   WSG 2.9: Optimize media to reduce resource use
5. Optimize web fontssave ~0.022 g/visit (199 kB)Medium impact · quick fix

   22 font files total 567 kB.

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

   • fa-solid-900.woff2159 kB
   • fa-brands-400.woff2119 kB
   • KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff243 kB
   • KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3KUBGEe.woff230 kB
   • 6xKtdSZaM9iE8KbpRA_hK1QN.woff229 kB

   WSG 2.11: Use optimized web typography
6. Reduce JavaScript payloadsave ~0.018 g/visit (159 kB)Medium impact · moderate effort

   15 scripts total 637 kB on the wire (664 kB 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.

   • bundle.js232 kB
   • swiper-bundle.min.js154 kB
   • jquery.min.js88 kB
   • flatpickr.js51 kB
   • owl.carousel.min.js44 kB

   WSG 3.2: Minify and remove unused codeWSG 3.3: Modularize bandwidth-heavy components
7. Audit third-party servicessave ~0.016 g/visit (144 kB)Medium impact · moderate effort

   4 third-party domains account for 288 kB (2% 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.

   • fonts.gstatic.com264 kB
   • cloud.axasora.com17 kB
   • fonts.googleapis.com4.7 kB
   • widgetbackend.axasora.com1.7 kB

   WSG 3.5: Treat third parties the same as first parties
8. Defer video and audiosave ~0.0066 g/visit (59 kB)Medium impact · quick fix

   1 video autoplays; 3 videos preload data without preload="none".

   Never autoload media: use preload="none" with a poster image, load players on interaction, and stream in an efficient codec (AV1/HEVC).

   • 2-gecmisten-gelecege-20250117-001112_4096x168…46 kB
   • 1-turkiyenin-en-koklu-20250617-163410_1920x79…28 kB
   • 12-bogazici-tanitim-20260126-134216.mp40 B
   • 12-bogazici-tanitim-20260126-134216.mp40 B
   • 1-turkiyenin-en-koklu-20250617-163410_1920x79…0 B

   WSG 2.9: Optimize media to reduce resource use
9. Fix caching for returning visitorssave ~0.0028 g/visit (19 kB)Medium impact · quick fix

   On a repeat visit 75 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.

   • 2-gecmisten-gelecege-20250117-001112_4096x168…no Cache-Control header · 46 kB
   • 1-turkiyenin-en-koklu-20250617-163410_1920x79…no Cache-Control header · 28 kB
   • axessora-widget.jsCache-Control: max-age=1 · 602 B
   • widget.jsCache-Control: max-age=1 · 289 B

   WSG 4.2: Optimize caching and support offline access
10. 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.txtThe host publishes a carbon.txt; its evidence has not reached the Green Web Foundation dataset yet.

    WSG 4.1: Use sustainable hosting
11. Set a page-weight budgetAdvisory · moderate effort

    At 13.74 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
12. Simplify the document structureAdvisory · larger effort

    The page renders 2056 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

• Images11.74 MB · 53 req
• CSS680 kB · 13 req
• JavaScript637 kB · 15 req
• Fonts567 kB · 22 req
• Audio / video74 kB · 12 req
• HTML36 kB · 1 req
• Data (fetch)1.7 kB · 2 req
• Other0 B · 2 req