Frequently asked questions about Webperf.se

General

Who is behind Webperf.se?

Webperf.se is run by Webperf AB. Behind the company stands Marcus Österberg, who has worked with web performance, accessibility and web standards since the late 1990s, and who started the Swedish webperf community before the company existed.

The test engine Webperf Core is not something the company owns. It has been a community project since 2019, under the MIT licence. Webperf AB uses it on the same terms as everyone else and contributes back to it.

What does it cost?

Being listed is free for websites that meet the criteria.

Webperf Cloud is a paid service giving more frequent tests, history, reports, an API, the ability to test your own environments, and support.

Do you sell consultancy?

No. Webperf AB doesn't sell consulting hours. What exists is Webperf Cloud, which includes support for your subscription, and the open source engine.

Scores and tests

How is the overall score calculated?

It's the average of the individual tests. Read more about grading.

Why do the scores differ between runs?

Dynamic content, networks, server load and external services all vary. More on that here.

Why don't your numbers match PageSpeed Insights?

Both run Google Lighthouse, but in different environments. Servers, throttling, hardware and cache state differ, and a 10–15 point gap is normal. What matters is the trend within one tool.

Which part of the website is tested?

Usually the start page. The exceptions are the 404 test, standard files and the accessibility statement. Read more.

How often are the tests run?

Webperf Cloud sites at least daily, others ahead of the monthly reports. More on testing.

My website

How do I get listed on Webperf.se?

If your website meets the criteria for the public sector or nationally important websites, listing is free. Suggest it. For private organisations, listing happens in connection with a Webperf Cloud account.

We got a bad score, what now?

1. Verify. Run the test again and compare with other tools.
2. Prioritise. Start with accessibility and security: that's where the consequences for visitors are greatest.
3. Read the review. Run with -r and you get a list of concrete problems instead of just a number.
4. Ask. The Slack channel is the fastest route to an answer.
5. Talk to the people who build the website before deciding what to do.

Your bot visited our website, is that normal?

Yes. The bot identifies itself as:

Mozilla/5.0 (compatible; Webperfbot/1.0; +https://webperf.se/om/#11)

Several tests drive real browsers and therefore use other user agents. More on testing.

Can we allowlist your IP addresses in advance?

Webperf Cloud customers can have testing from static IP addresses and get the address list when the feature is enabled. Read more.

Web agencies

How do we get on the web agency list?

The web agency category requires a Webperf Cloud account and that the website matches the category's criteria. More about categories.

Is there a volume discount?

Yes. Webperf Cloud for agencies covers up to 21 websites in a single account.

Technical questions

Which browsers are used?

Chrome and Firefox, depending on the test. Chrome is the default and can be changed with tests.sitespeed.browser.

Why does the wrong country show up in the security tests?

If you use a CDN, traffic from different test servers may be handled differently, and the CDN may answer from a node in another country. That affects the privacy assessment. More on testing.

Do you support IPv6?

Yes. Several IPv6 checks are still off by default. The environments the tests run in often lack IPv6. GitHub Actions, for instance, doesn't have it. Turn them on locally:

python default.py -u https://example.com -t 24 \
  --setting tests.email.support.ipv6=true

The DNS test has its own equivalent, tests.dns.ipv6.