Last updated: September 14, 2026.
Between July 28 and August 16, 2026, we measured 278 sustainable business websites: the homepages of sustainable businesses and environmental organizations, most of them in Colorado. Nearly half earned an A or A+ carbon rating. Only one in three runs on green hosting, 30% of the homepages weigh more than 2 MB, and 37% have no meta description at all.
This report shares the aggregate results only. No business is named, and neither our own site nor our clients are in the sample.
The findings at a glance
| What we measured | Result |
|---|---|
| Homepages rated A or A+ for carbon per visit | 49% (136 of 278) |
| Homepages rated F | 15% (41 of 278) |
| Sites on hosting verified as green | 33% (93 of 278) |
| Median homepage weight | 1.26 MB |
| Homepages heavier than 2 MB | 30% (81 of 271) |
| Homepages under 500 KB rated A or A+ | 100% (all 60) |
| Homepages over 4 MB rated F | 82% of 38 |
| Median CO2 per visit | 0.19 grams |
| Homepages with no meta description | 37% (104 of 278) |
| Loads well for real visitors, where Google has that data | 84% (103 of 122) |
Where the sample comes from
We built the sample from public business listings of sustainable businesses and environmental organizations, and measured one homepage for each. Most of these sustainable business websites are in Colorado: 189 of the 278. Oregon adds 41, Texas 33 and California 15, and those four states make up the whole sample.
The overall figures therefore mostly describe Colorado businesses. Only three states reach 25 or more sites, enough to compare, and California’s 15 are too few.
| State | Sites | Rated A or A+ | Rated F | Median homepage weight | Verified green hosting |
|---|---|---|---|---|---|
| Colorado | 189 | 39% | 20% | 1.29 MB | 30% |
| Oregon | 41 | 59% | 2% | 1.48 MB | 39% |
| Texas | 33 | 73% | 6% | 703 KB | 45% |
Texas homepages were the lightest group and the most likely to reach A or A+. Oregon homepages were heavier than Colorado’s at the median, yet reached A or A+ more often and almost never landed at F. A median hides the heaviest pages in a group, and those are the pages that tend to end up at F.
Read these as patterns in this sample, not rules about any state. The Oregon and Texas groups are small enough that a few sites move their percentages noticeably, and the figures describe these sustainable business websites, not every business in those states.
Carbon ratings: half the sample already gets it right
Ratings follow the Sustainable Web Design digital carbon rating bands, from A+ for the lowest carbon per visit to F for the highest. The distribution is wider than most people expect.
| Rating | Homepages | Share |
|---|---|---|
| A+ | 68 | 24% |
| A | 68 | 24% |
| B | 34 | 12% |
| C | 37 | 13% |
| D | 18 | 6% |
| E | 12 | 4% |
| F | 41 | 15% |
Two readings matter. First, a low carbon homepage is clearly achievable for sustainable business websites: 136 of the 278 sites reached A or A+. Second, one in four sits at D or below, and 41 homepages landed at F, which puts a quarter of the sample well behind peers selling to the same conscious buyers.
Green hosting is still the exception, and it does not decide the rating on its own
Only 93 of the 278 sustainable business websites, 33%, run on hosting verified as green. For businesses whose entire pitch is environmental, that is a visible gap, and one a well informed buyer can check in a few seconds.
Hosting on its own did not decide the rating, though. Among sites on green hosting, 53% earned an A or A+ and 11% an F. Among the rest, 47% earned an A or A+ and 17% an F. The host changes the electricity behind each visit; how much the page makes every visitor download changes the result more.
Where does your own site sit? Run your homepage through our free Website Carbon Checker to see its rating, the grams of CO2 per visit and whether your hosting is verified as green, then compare it with the numbers above.
Page weight decides most of the result
The median homepage among these sustainable business websites weighs 1.26 MB. 38% stay under 1 MB, while 30% go past 2 MB and a quarter of the sample passes 2.4 MB. For context, the HTTP Archive’s 2025 Web Almanac puts the median mobile page on the web at 2.56 MB, and 24% of these homepages are heavier than that.
Carbon follows weight closely. The median homepage produces 0.19 grams of CO2 per visit, while the heaviest quarter produces more than half a gram. Images, video, web fonts and third party scripts are where that weight usually lives. What sustainable web design is, and how a site is measured explains which of those moves the number most.
Weight bands versus rating: the strongest pattern in the data
Grouping the 271 homepages with a weight reading into five bands shows how closely the rating tracks weight. Every one of the 60 sustainable business websites under 500 KB earned an A or A+. So did 77% of homepages between 500 KB and 1 MB and 41% between 1 and 2 MB, and not one above 2 MB.
| Homepage weight | Sites | Rated A or A+ | Rated F | Median CO2 per visit |
|---|---|---|---|---|
| Under 500 KB | 60 | 100% | 0% | 0.05 g |
| 500 KB to 1 MB | 44 | 77% | 0% | 0.10 g |
| 1 to 2 MB | 86 | 41% | 0% | 0.23 g |
| 2 to 4 MB | 43 | 0% | 23% | 0.40 g |
| Over 4 MB | 38 | 0% | 82% | 2.25 g |
F ratings sit at the other end: none under 2 MB, 23% between 2 and 4 MB and 82% over 4 MB. The median carbon per visit climbs with every band, from 0.05 grams for the lightest homepages to 2.25 grams for the heaviest.
For sustainable business websites, homepage weight is the closest thing to a rating lever the business controls. The exact weight and the hosting still vary inside each band, which is why the 1 to 2 MB band splits between A or A+ and lower grades.
How much carbon that adds up to over a year
A single visit to most sustainable business websites produces very little carbon. The quarter point is 0.10 grams of CO2 per visit, the median 0.19 grams and the 90th percentile 1.37 grams. A quarter of homepages stay under 0.10 grams, while 13% pass 1 gram.
Visits add up, though. As an estimate for illustration only, at 10,000 homepage visits a month a median homepage would account for about 23 kg of CO2 a year, and a 90th percentile homepage for about 164 kg. Real traffic and caching change those figures, so read them as scale, not measurement.
Weight is also concentrated: the heaviest 10% of homepages carry 61% of all the bytes in the sample, and bytes are what the carbon estimate is built on. For a business with a heavy homepage, the first megabytes taken out matter more than fine tuning a page that is already light.
The platform matters less than how the site is built
We could identify the platform on 203 of the sustainable business websites. WordPress runs just over half of them.
| Platform | Sites | Median homepage weight | Heavier than 2 MB |
|---|---|---|---|
| WordPress | 104 (51%) | 1.21 MB | 38% |
| Squarespace | 35 (17%) | 1.34 MB | 23% |
| Shopify | 32 (16%) | 1.22 MB | 28% |
| Wix | 19 (9%) | 1.41 MB | 11% |
| Webflow | 13 (6%) | 1.63 MB | 46% |
The medians sit close together, between 1.2 and 1.6 MB, so no platform guarantees a light site or condemns a heavy one. The share of heavy homepages varies more, and the Webflow and Wix groups are small enough that we would not draw a conclusion from them. What the page loads decides the result, whichever platform serves it.
Platform deep dive: ratings, meta descriptions and hosting
Broken down by rating, meta description and hosting, the 203 sustainable business websites with a known platform separate more clearly. The platform was unknown on 75 sites, and the Wix and Webflow groups are small.
| Platform | Sites | Rated A or A+ | Rated F | No meta description | Verified green hosting |
|---|---|---|---|---|---|
| WordPress | 104 | 45% | 24% | 31% | 40% |
| Squarespace | 35 | 29% | 6% | 57% | 0% |
| Shopify | 32 | 59% | 3% | 16% | 97% |
| Wix | 19 | 37% | 0% | 21% | 11% |
| Webflow | 13 | 46% | 31% | 85% | 0% |
On Squarespace, Shopify, Wix and Webflow the platform runs the servers, so the green hosting share reflects where each platform’s servers are listed by the Green Web Foundation, not a choice each business made. On WordPress the business or its developer usually picks the host, so its 40% reflects many separate decisions.
WordPress. 45% rated A or A+ and 24% rated F. Owners control the theme, plugins, image sizes and the host. WordPress core has no meta description field, so one usually comes from an SEO plugin or the theme.
Squarespace. The lowest A or A+ share, 29%, but only 6% rated F. Hosting and most of the code come with the platform, so the levers are image sizes, video backgrounds, galleries and embeds, plus a meta description setting that 57% of these homepages did not use.
Shopify. The highest A or A+ share, 59%, with 3% rated F and the fewest missing meta descriptions, 16%. Owners still decide what the homepage loads: apps that add scripts, product imagery, video and theme sections.
Wix. No homepage rated F and 37% reached A or A+, in a small group of 19. Owners control images, video, animations and added apps, while hosting comes with the platform.
Webflow. The smallest group, 13 sites, and the most divided: 46% rated A or A+, 31% rated F and 85% had no meta description. Interactions, custom fonts and background video all add weight, and each one is a design choice.
37% of homepages have no meta description
104 of the 278 sustainable business websites have no meta description on their homepage, so Google writes its own snippet from whatever text it finds on the page. For a business competing on trust, that means the first sentence a searcher reads was not chosen by the business. It is one of the website fixes a sustainable brand can make without a rebuild.
It is a search issue, not a carbon one. Among sustainable business websites in this sample, 46% of homepages with a meta description earned an A or A+ (174 sites), against 54% of those without one (104 sites). The two are unrelated here: writing one will not move a rating, but it gives the business a say in how its homepage appears in search.
Speed: what real visitors experience
Google publishes real visitor speed data only for sites with enough traffic, and it had that data for 122 of the sites we tested for speed. 103 of them, 84%, loaded well for their visitors, and 19 were slow. For the other sites only a simulated test was available, and a simulation on a throttled phone connection is not the same thing as what customers experience, so we left those results out rather than overstate the problem.
Lab tests versus real visitors: why the speed numbers disagree
PageSpeed Insights reports two different things. The lab test loads the page once on a simulated mid-range phone over a throttled connection. The field data, published only for sites with enough traffic, records how the page loaded for real Chrome users over the previous 28 days.
Our readings show the gap. The median lab score was 57 out of 100 across 282 readings: 29% scored under 50 and 5% reached 90 or above. Sites with only lab data (113) showed a median Largest Contentful Paint, the moment the largest piece of content appears, of 12.5 seconds in the throttled simulation. Sites that load well for real visitors (103) showed a median of 1.8 seconds.
These are different groups of sites, so this is not a like-for-like comparison, and sites with little traffic may well be slower in practice. Still, a throttled simulation paints a harsher picture than most customers experience, which is why this report counts real visitor data and uses lab scores to find what to fix.
Check your own site against 278 sustainable business websites
Five checks place your homepage within this group.
1. Weigh the homepage. Our free Website Carbon Checker reports the megabytes transferred per visit. A quarter of homepages here weigh under 580 KB, half under 1.26 MB and three quarters under 2.41 MB. Under 500 KB, every one rated A or A+; over 2 MB, none did.
2. Place the rating. The same check gives the rating and the grams of CO2 per visit. Here, 49% of sustainable business websites rated A or A+ and 15% rated F. A quarter came in under 0.10 grams, half under 0.19 grams, and one in ten passed 1.37 grams.
3. Verify the hosting. The checker also shows whether your host is verified as green; two in three sites here were not. On Squarespace, Shopify, Wix or Webflow, that depends on where the platform’s servers are listed. On WordPress, it depends on the host you chose.
4. Confirm the meta description. View your homepage’s source and search for name=”description”. If the tag is not there, your homepage is in the 37% of this sample that leaves its search snippet to Google.
5. Look at Core Web Vitals in Search Console. It shows how real visitors experience your pages once the site has enough traffic; 84% of the sites with that data loaded well here. Without that data, treat the PageSpeed Insights lab test as a list of fixes, not a verdict.
If more than one check lands behind the sample, send us your website and get a plan and a quote to close the gap within 24 hours.
What to do with these numbers
1. Weigh your homepage before anything else. Weight moved the rating more than any other factor in this sample. Start with images and video, then fonts and scripts nobody remembers adding.
2. Check your hosting. Two in three sites here are not on verified green hosting. Our guide to green web hosting providers covers how to verify a host’s claim.
3. Write the meta description for your homepage and main pages. Choose the sentence a searcher reads first instead of leaving it to Google.
4. Watch real visitor speed, not only lab scores. The Core Web Vitals report in Google Search Console shows what actual visitors experience once your site has enough traffic.
5. If a rebuild is coming, set a weight budget from the first meeting. It is far harder to take weight out of a finished site than to keep it out. That is how we approach every project as a sustainable web design agency.
How we measured
Sample. 278 sustainable business websites, one homepage each, from sustainable businesses and environmental organizations found through public business listings and measured between July 28 and August 16, 2026. 189 are in Colorado, with 41 in Oregon, 33 in Texas and 15 in California. It is not a random sample of the web: it reflects businesses that present themselves as sustainable or environmentally focused.
Carbon and hosting. Each homepage was measured once with our Website Carbon Checker, which estimates grams of CO2 per visit from the data transferred using the Sustainable Web Design Model, rates the result on its A+ to F bands, and reports whether the hosting is verified as green. The method is described at sustainablewebdesign.org.
Weight and platform. Weight is the data transferred when the homepage loads; 271 of the 278 returned a value. The platform was identified from the page code on 203 sites.
Speed. Google PageSpeed Insights, counting only real visitor data from sites where Google publishes it; lab scores appear only as a contrast. The speed readings cover a slightly wider set than the 278 homepages in the carbon results.
Limits. One homepage per business, measured once, so inner pages, shop pages and seasonal changes are not reflected. The sample leans heavily on Colorado, so state differences are patterns rather than rules. Ratings use the Sustainable Web Design bands as our checker applies them, and other calculators may band a page differently. The yearly carbon figures are illustrations, real visitor data only exists for sites with enough traffic, and the results describe this group of sustainable business websites, not the web as a whole.
Frequently asked questions
Which websites were included in this report?
278 sustainable business websites: the homepages of sustainable businesses and environmental organizations we measured between July 28 and August 16, 2026, most of them in Colorado, with others in Oregon, Texas and California.
Why are no companies named?
The point of the report is the pattern across the group, not any single business. Every figure is an aggregate, and neither Planet Media’s own website nor our clients are in the sample.
What does an A+ carbon rating mean?
It is the lowest carbon band on the Sustainable Web Design rating scale, based on the estimated grams of CO2 produced each time the page is visited. F is the highest band.
Does green hosting guarantee a good carbon rating?
No. Among these sustainable business websites, 53% of sites on green hosting earned an A or A+, against 47% of the rest. Hosting changes the electricity behind each visit, while page weight changes how much energy each visit needs.
Why did you only count real visitor speed data?
Simulated tests run on a throttled phone connection and tend to be much harsher than what visitors actually experience. Counting them would have overstated the problem, so the speed figures use real visitor data only.
How can I check my own website?
Run your homepage through our free Website Carbon Checker for the rating and hosting status, or send us your website for a plan and a quote across positioning, design, conversion, speed and search.
How heavy can a homepage be and still rate A or A+?
In this sample, every homepage under 500 KB rated A or A+, as did 77% of those between 500 KB and 1 MB and 41% of those between 1 and 2 MB. None over 2 MB did, so staying under 1 MB was the clearest route to the top two ratings among these sustainable business websites.
How much CO2 does a homepage produce in a year?
It depends on weight and traffic. As an estimate for illustration, at 10,000 visits a month a homepage at this sample’s median of 0.19 grams per visit would account for about 23 kg of CO2 a year, and one at the 90th percentile, 1.37 grams, about 164 kg.
Why does my PageSpeed lab score look worse than my real visitor data?
The lab score comes from one simulated load on a mid-range phone over a throttled connection, which is harsher than what most visitors experience; in our readings the median lab score was 57 out of 100. Search Console’s Core Web Vitals report reflects real visitors, so use the lab test to find fixes and that report to judge performance.
Kurt Whitt
Planet Media
Founder and CEO of Planet Media, a sustainability focused marketing agency. 25+ years helping purpose driven brands grow through strategy, storytelling and design.
More about the team