C
Cache header A cache header is the server response header that tells the browser how long a resource may be stored and how it is to be revalidated. Performance
Canonical address A canonical address is the markup declaring which page is the original when the same or very similar content is reachable from more than one address. Multilingual
Certificate scope A certificate’s scope is the description on the certificate that states which activities, products and sites it covers. Certified manufacturing
Citation A citation is an answer engine mentioning a source in the answer it produces, usually with a link to it. Answer engines
CLS (Cumulative Layout Shift) measures how much content shifts unexpectedly while a page is loading or in use, and Google counts anything under 0.1 as good. Performance
Colour blindness is the inability to tell certain colours apart, and it affects a considerable share of the world’s population, men in particular. Accessibility
Compression is the shrinking of text-based resources before they are sent from the server and their expansion in the browser. Performance
Conversion rate is the ratio of visits or interactions in which the desired action on a site (quote form, sample request, purchase) is completed to all visits or interactions. Certified manufacturing
What is a conversion rate?
Conversion rate is the ratio of visits or interactions in which the desired action on a site (quote form, sample request, purchase) is completed to all visits or interactions.
The definition is simple, but the denominator varies by tool, which is why rates cannot be compared across tools. In Google Ads, conversion rate is the average number of conversions per ad interaction. In Google Analytics 4, the equivalent is the session key event rate: the ratio of sessions with a key event to all sessions. In Microsoft Advertising, it is conversions as a share of clicks. When several conversions are counted, the rate can even exceed 100%.
Which conversion should a manufacturer measure?
The one closest to the sale: submitting the quote form or requesting a sample. Page views, scrolling or catalog downloads are intermediate steps; they can be measured too, but they should not be counted in the conversion rate’s numerator. Defining the quote form as a key event in the analytics tool makes it clear what the rate counts.
Can other sites' conversion rates be a target?
With care. There is a published visitor-to-lead rate for manufacturing, 2.2%; but it is a marketing agency’s own client data, and the number of clients is not disclosed. Another report giving a median of 6.6% across all sectors measures only landing pages, not the whole site. Both point in a direction; your site’s target comes from your own past data.
- Write down the denominator: sessions, users or clicks?
- Write down the numerator: which action counts as a conversion?
- Write down the period: the rate for which range?
- Compare with the same tool and the same definition.
If the conversion rate is low, what should be checked first?
- Does the form work? Test it with your own submission and check that it shows up in the analytics tool.
- Does the form open and submit on a phone?
- Is the measurement correct? An old analytics tag or an incompletely defined key event can show the rate as zero.
- Is the form longer than necessary? Every required field is a point at which people give up.
- Is the visitor arriving on the right page? If an ad or a QR code leads to the home page, the visitor may not find what they are looking for.
Conversion rate is an outcome measure; it does not tell you the cause. To see at which step people give up when the rate falls, opening the form, filling in the first field and submitting can be measured separately.
Adding a source parameter to the address to measure where a visit comes from also makes the rate meaningful; there is an example in the trade fair QR landing page guide.
How lost inquiries and the break-even point are calculated from the conversion rate is covered in the true cost of a cheap website guide.
For a site that shows your certificates as a record buyers can verify, B2B website builds and measures the certificate page, the product scope and the path to a quote together.
Certified manufacturing
Core Web Vitals is the collective name for the three metrics Google defined to measure a page’s real user experience. Performance
Country domain (ccTLD) A country domain is a two-letter top-level domain extension allocated to a particular country. Multilingual
Crawl budget is the number of requests a search engine allocates to fetching from a site within a given period. Answer engines
Critical rendering path The critical rendering path is the minimum sequence of steps a browser must complete before it can draw a page on screen. Performance
D
Digital product passport A digital product passport is the record that electronically links to a product the product information to be specified separately for each product group under the EU’s Ecodesign Regulation (ESPR). Certified manufacturing
E
EN 301 549 (Accessibility requirements for ICT products and services) is the European standard, published jointly by CEN, CENELEC and ETSI, that defines the accessibility requirements for information and communication technology products and services and how they are to be tested. Accessibility
Entity An entity means a distinct thing that search and answer engines recognise — a person, an organisation, a place, a product or a concept. Answer engines
EU declaration of conformity An EU declaration of conformity is the document, drawn up and signed by the manufacturer or its authorized representative, in which the manufacturer declares under its own responsibility that a product meets the requirements of the EU legislation that applies to it. Certified manufacturing
F
Field data is the sum of performance measurements experienced by real users on real devices and real networks. Performance
Focus trap A focus trap is when keyboard focus enters a region and cannot leave it again, and WCAG prohibits it explicitly at level A. Accessibility
Font subset A font subset is a font file regenerated with only the characters that are needed. Multilingual
G
GEO (Generative Engine Optimization) is the work of increasing the likelihood that a site is chosen as a source in the answers generated by AI systems. Answer engines
Global ACI (Global Accreditation Cooperation Inc.) is the organization that runs the international mutual recognition arrangement of accreditation bodies and replaced IAF, which ceased operations on January 1, 2026. Certified manufacturing
H
hreflang is the markup that declares a page’s different language and region versions to search engines. Multilingual
I
Index (search index) The index is the database in which a search engine keeps the pages it has decided to store out of those it crawled, and the only place it selects search results from; it is also called the search index. Being found on Google
IndexNow is an open protocol that tells search engines immediately that a page has changed. Answer engines
INP (Interaction to Next Paint) is the time from a user interaction until the page responds visually, and Google counts anything under 200 milliseconds as good. Performance
ISO/IEC 17025 is the international standard that sets the requirements for the competence, impartiality and consistent operation of testing and calibration laboratories, and on which laboratory accreditation is based. Certified manufacturing
J
JSON-LD (JavaScript Object Notation for Linked Data) is a structured data format that declares a page’s meaning in a machine-readable form without changing the page’s appearance at all. Answer engines
L
Language tag (BCP 47) A language tag is the standard coding form that tells machines which language a text is in. Multilingual
LCP (Largest Contentful Paint) is the paint time of the largest content element in a page’s visible area, and Google counts anything under 2.5 seconds as good. Performance
Live region A live region is an area of a page whose changes a screen reader has to announce to the user. Accessibility
llms.txt is an optional file placed in a website’s root directory that summarises, in Markdown, what the site is about and where its most important pages are for language models. Answer engines
Locale A locale is the setting that defines a user’s language and region together and determines the formatting rules. Multilingual
Localisation (Localization) is adapting content to the culture, habits and search language of a target market; it is a wider undertaking than translation. Multilingual
M
Mobile-first indexing means that Google bases indexing and ranking of a page on the version of the page shown to its smartphone crawler. Certified manufacturing
N
noindex is a directive asking that a page not be added to a search engine’s index, given either with the robots meta tag inside the page or with the server’s X-Robots-Tag response header. Being found on Google
R
Redirect chain A redirect chain is when an address reaches its final address not in a single hop but by passing through more than one redirect; for example, if an old address is redirected first to an intermediate address and from there to the final address, there is a two-hop chain. Site migration
Reflow A reflow is the browser recomputing the positions and sizes of elements on a page after a change. Performance
Relative luminance is the value expressing a colour’s perceived lightness between 0 and 1, and it is the basis of the contrast ratio calculation. Accessibility
S
Screen reader A screen reader is assistive technology that turns on-screen content into speech or braille output and lets the user navigate by keyboard. Accessibility
Search Console is a free service from Google for monitoring a site’s status in Google Search and for seeing and fixing its problems. Being found on Google
Semantic HTML means choosing each element for its meaning rather than its appearance — a heading element for a heading, a button element for a button, a list element for a list. Accessibility
Sitemap A sitemap is a file, usually written in XML, that lists the addresses of a site’s pages and, optionally, their last modification dates for search engines in a single file. Being found on Google
Social compliance audit A social compliance audit is the examination by an independent auditor of working conditions, occupational health and safety and business ethics at a production site against a code of conduct. Certified manufacturing
Soft 404 A soft 404 is a page that shows visitors “page not found” or empty content but returns a 200 (success) code from the server instead of an error code; Google treats these pages as error pages and does not index them. Site migration
Structured data is an additional layer that labels a page’s content with a standard vocabulary machines can understand. Answer engines
T
Text expansion is the same content being of different lengths in different languages, and the layout having to flex accordingly. Multilingual
TLS certificate lifetime is the period from the day the certificate that provides a site’s HTTPS connection is issued to the day its validity ends. Certified manufacturing
Total cost of ownership is the sum of all the costs of buying an asset or service and using it over its service life. Certified manufacturing
Transaction certificate A transaction certificate is the document, issued by a certification body under Textile Exchange standards, that shows a specific delivered consignment of goods is certified. Certified manufacturing
Translation memory A translation memory is a database that stores previously translated sentences and suggests them when the same or a similar sentence comes up again. Multilingual
TTFB (Time to First Byte) is the time between the browser sending a request and receiving the first byte from the server. Performance
U
URL inventory A URL inventory is a single list that gathers every address of a site that search engines know — current pages, address variants and old addresses; in a site redesign or migration, the redirect map is derived from this list. Site migration
W
WCAG (Web Content Accessibility Guidelines) is the international standard published by the W3C that defines the accessibility of web content through testable success criteria. Accessibility
X
x-default is a special hreflang value declaring the default page to show when no language version matches the user’s language. Multilingual