Fashion certifications are a small industry in themselves, and not all of them do the same job. A brand waving a certification logo is not necessarily a credible brand; it depends on which certification, for what part of the supply chain, audited by whom. This is the plain-English guide to the four that matter most, what each actually certifies, and what each does not.
GOTS — Global Organic Textile Standard
The strongest certification for organic fibres in textiles. GOTS certifies that a garment contains at least 70% organic fibre (Organic grade = 95%+; Made with organic = 70-94%) and that the processing — dyeing, finishing — meets environmental standards. It also includes some social criteria on factory labour, though labour is not its primary focus.
Strong on: materials, chemical use, processing.
Softer on: worker pay, specific factory conditions.
Absent from: carbon, transport, end-of-life.
OEKO-TEX Standard 100
A chemical-safety certification. OEKO-TEX tests finished fabric for harmful substances — heavy metals, formaldehyde, pesticides, known allergens. It is thorough on what it tests for but narrow: it says nothing about how the fabric was grown, who made the garment, or what the brand's practices are.
OEKO-TEX is useful as a baseline safety check, particularly for anything that touches the skin directly. It is not a sustainability certification.
Fair Wear Foundation
The serious one for labour. Fair Wear audits garment factories against a Code of Labour Practices covering pay, working hours, health and safety, forced and child labour, freedom of association, and discrimination. Brands that are Fair Wear members commit to sourcing from audited factories and are themselves rated annually on how well they are implementing the code.
Strong on: labour, workplace conditions, ongoing brand accountability.
Softer on: environmental / materials side.
A Fair Wear brand rating of Good or Leader is a genuinely strong labour signal. A brand using "Fair Wear member" but not disclosing the rating is often a lower-rated member.
B Corp
Certification of the whole business, not the product. B Corp measures social and environmental performance across governance, workers, community, environment, and customers. A B Corp brand has passed a threshold score and has legally committed to consider stakeholder impact, not just shareholder return.
B Corp is a good overall corporate-behaviour signal, but it is not product-specific. A B Corp brand can still source from factories with middling labour practices and sell garments made of fast-fashion materials. B Corp + GOTS or B Corp + Fair Wear is a stronger combination than B Corp alone.
What no certification covers
None of the four certifications above covers carbon emissions in full. None covers end-of-life (what happens to the garment when you throw it away). None fully covers transparency downstream (who you are buying from, what they buy from, and so on).
These gaps are why the Fashion Transparency Index exists as a separate tool. It measures disclosure rather than certification — how much a brand publishes about its supply chain — and often reveals that heavily certified brands are still opaque on large parts of their operation.
The practical reading
A credible brand will usually have one or two of these certifications and will be honest about what they do not have. A brand with none, buying claims vaguely, is almost certainly greenwashing. A brand with all four is possible but rare and worth investigating for authenticity — sometimes the list is real, sometimes the list is marketing.
Small makers often have none of these because the audit fees are prohibitive. That does not make them worse — it makes them unable to buy the logos. A transparent small maker, with photos of their workshop and named fabric suppliers, can be as credible as a certified large brand, sometimes more so.
Full slow-vs-sustainable-vs-ethical context in the pillar guide.