How Green Is Your Website? WordPress vs Static Carbon Footprint

The web feels weightless. You open a page, it appears, nothing is burned in front of you. But somewhere a data centre, a network and your own device all drew a little electricity to make that happen, and most of the world's electricity is still made with some fossil fuels. Multiply one small page view by the billions that happen every hour and the internet quietly becomes a real source of emissions, on the order of a couple of percent of global greenhouse gases, similar to the aviation industry.

That's not a reason to feel guilty about having a website. It's a reason to build it well. This is the honest, research-backed version of the story: how a page turns into CO2, why a static site is dramatically more efficient than WordPress, what that saves for a real small business, and what it adds up to as we grow. We'll also be upfront about which numbers are solid and which are genuinely contested, because a green claim you can't defend is worse than no claim at all.

Check your own site in seconds

Paste your address below. We measure your real page weight, estimate your yearly carbon footprint, and show what a fast static site could save. The rest of this article explains exactly how the numbers work.

How a web page turns into CO2

The standard way the industry estimates this, used by the Website Carbon Calculator and the Sustainable Web Design Model, is a simple chain:

In plain terms: a heavier page moves more data, moving data uses energy, and energy has a carbon cost that depends on how clean the local grid is. The current model (version 4, adopted in mid-2025) puts the energy at about 0.30 kWh per gigabyte across the whole journey and uses a global average grid of 494 grams of CO2 per kWh. That works out to roughly 0.15 to 0.3 grams of CO2 for an average page view.

One honest note before we go further: that latest model produces estimates about two-thirds lower than the previous one, because the internet has become more efficient per byte. So if you've seen older headlines claiming "half a gram" or "1.76 grams" per page view, treat them as an out-of-date upper bound. The web is getting cleaner per page; the lever you control is how much data your page sends and how much work your server does.

Why WordPress costs more than static, measured

Here's the part with the strongest evidence. A WordPress page is built fresh on every single visit: the server runs PHP, queries a database, assembles the page from a theme and plugins, and only then sends it. A static page is already finished, so the server just hands over a file. Same visitor, a fraction of the work.

A 2024-25 engineering study measured exactly this, putting identical traffic through different setups on a controlled testbed and reading the actual power draw. The gap is not subtle:

Two findings stand out:

• Up to ~60x less power. At the same traffic, the dynamic WordPress setup peaked around 27 watts while the static equivalent stayed under 1 watt. A lighter dynamic app (a simple Flask blog) still used around 9 times more power than its static version.
• Far more visitors per server. The static site comfortably served thousands of requests per second where the dynamic one hit a ceiling in the low tens. In other words, one green-powered server does the work of many, which is efficiency you don't even see on your own bill.

On top of the server saving, static pages are usually lighter. A typical plugin-heavy WordPress page can weigh 2 to 3 MB; a clean static version of the same page is often half that or less. That directly shrinks the "data" term in the CO2 formula above, on every single visit. (If you want the full non-environmental case for static, we cover it in static websites: benefits and weaknesses.)

The honest caveat: some of these numbers are soft

We promised honesty, so here it is. The server workload reduction above is well-measured and robust. The per-view carbon figure is softer. Peer-reviewed research (Mytton, 2024, in the Journal of Industrial Ecology) shows that network energy use is not simply proportional to the gigabytes transferred, the network runs at a high baseline whether your page is 1 MB or 3 MB, so the "energy per gigabyte" figure these calculators use varies enormously between studies.

What that means in practice: treat any single CO2-per-page number as a range, not a fact. The trustworthy, defensible headline isn't "your page emits exactly X grams", it's "a static site does far less server work and moves less data than the WordPress site it replaces". That claim is measured, repeatable and hard to argue with.

What it saves for one real website

Let's make it concrete with clearly stated assumptions, so you can check the maths:

• A WordPress page ~2.5 MB, its static version ~1.0 MB, so about 1.5 MB lighter per view.
• At ~0.30 kWh/GB and a 494 g/kWh grid, that's roughly 0.22 grams of CO2 saved per visit.
• A small business site getting ~10,000 page views a month sees about 26 kg of CO2 a year saved from lighter pages alone.

Depending on traffic and how heavy the old site was, that's realistically 5 to 50 kg of CO2 a year per site, before you even count the much larger reduction in server workload, which is real but harder to pin to a single site because shared hosting packs many sites onto one machine. Per site, this is a nice-to-have, not a headline. The story gets interesting when you multiply it.

Our mission, and what a million pages means

ShiftPress exists to move the web off the slow, heavy, high-maintenance stack it got stuck on, and onto fast, efficient code, without forcing anyone to become a developer. We wrote about where this is heading in The Next Era of the Web. Part of that mission is a concrete target: host one million pages on clean, static architecture by 2030.

What would that save? Being deliberately conservative and counting only the lighter-page effect (not the bigger server-workload win), and stating the obvious dependency, it all hinges on how much those pages are actually visited, the range lands on the order of:

Tonnes of CO2 are hard to picture, so here's what the central estimate of ~100 tonnes a year looks like in everyday terms (using U.S. EPA equivalency factors):

• ≈ 23 cars taken off the road for a whole year.
• ≈ 100 acres of forest quietly absorbing CO2 for a year.
• ≈ the yearly electricity of 21 homes.

At the optimistic end (~300 tonnes) it's more like 70 cars or 300 acres of forest. These are estimates with the assumptions on the table, not a marketing round-up, and the real number depends heavily on traffic and how clean the hosting grid is. But the direction is not in doubt: efficient sites, at scale, keep a meaningful amount of carbon out of the air, as a side effect of simply being better websites.

How ShiftPress makes "green" the default

The nice thing about efficiency is that you don't have to choose it. With ShiftPress you get it automatically, because it's the same thing that makes your site fast and cheap to run:

• Static by default. We turn your WordPress site into a static one served from a CDN, so there's no per-visit database or PHP work.
• Lighter pages. No plugin bloat, no render-blocking theme machinery, so less data moves on every view.
• Hosted in the EU (Frankfurt). Your data and delivery stay on European infrastructure.
• No maintenance overhead. Nothing to keep patched and running around the clock just in case someone visits.
• Still fully editable. An AI editor sits on top, so the old downside of static, "but how do I change it?", is gone. You talk, it edits, it publishes.

You don't move to ShiftPress to save carbon. You move because your site becomes faster, safer and cheaper to run, and lower emissions come along for the ride. That's the kind of sustainability that actually sticks: the one that's also the better business decision.

Frequently asked questions

The bottom line

A website's carbon footprint is small per visit and easy to ignore, but it's real, and it scales with every page and every visitor. The single biggest lever an ordinary business has is the one that also makes the site faster, safer and cheaper: stop rebuilding every page on every visit, and serve finished, lightweight files instead. A static site does far less work for the same result. Across one page it's a rounding error. Across a million, it's a small forest. And with an AI editor on top, you finally get all of that without giving anything up.