What Is Colorfastness? Fabric Color Testing Guide

What colorfastness means, the main AATCC and ISO 105 tests for washing, crocking, light and perspiration, how grey scale grades work, what causes bleeding and fading, and how to specify colorfastness on a clothing or textile order.

The Short Answer

Colorfastness is how well a dyed or printed fabric keeps its color when it is washed, rubbed, exposed to light, wet, or worn against sweat. A fabric with good colorfastness does not fade noticeably, does not bleed into the wash water or onto other garments, and does not leave color on skin, seats or a white shirt underneath. It is also written color fastness, colour fastness or colourfastness. The meaning is the same.

For a brand, colorfastness is not an abstract lab property. It is the difference between a navy hoodie that still looks navy after twenty washes and one that turns a white load pale blue, prompts a return, and earns a one-star review. It is measured with standard tests, graded on a numbered scale, and agreed with the factory before production. This guide explains the main colorfastness tests for apparel and home textiles, how results are graded, what causes poor results, and how to specify and check colorfastness on a private label order.

Why Colorfastness Matters for a Clothing or Textile Order

Most color complaints from customers fall into a few patterns, and each one maps to a specific test:

Bleeding in the wash. A garment releases dye into the water and stains other items. This is colorfastness to washing, specifically the staining part of the result.

Fading. The color becomes lighter or duller after repeated washing or time in sunlight. This is color change after washing or after light exposure.

Rub-off or crocking. Color transfers when the fabric is rubbed, for example dark jeans onto a sofa, or a black T-shirt onto a light bag strap. This is colorfastness to rubbing, also called crocking.

Color transfer from sweat. Underarms or waistbands discolor, or color moves onto skin or a lighter layer. This is colorfastness to perspiration.

Color change at the pool or beach. Swimwear and beach towels fade or shift shade in chlorinated or salt water.

None of these problems is visible when the goods arrive. A shipment can match the approved color standard perfectly on delivery and still fail in a customer's washing machine. That is why colorfastness is tested, not inspected by eye, and why the requirement belongs in the specification rather than being left to the factory's default.

The Main Colorfastness Tests for Apparel and Home Textiles

Colorfastness tests are published by two main bodies. AATCC (the American Association of Textile Chemists and Colorists) methods are widely used by US brands and retailers. ISO 105 methods are widely used in Europe and by many mills worldwide. The two families measure similar properties with different procedures, so results under one are not automatically equivalent to the other. Specify which method you want.

Colorfastness to washing (laundering)

This is the most commonly requested test for clothing, towels and bedding. A specimen is washed under controlled conditions together with a multifiber test fabric, a strip woven from several different fibers such as cotton, nylon, polyester, acrylic, wool and acetate. Afterwards, the lab assesses two things: how much the specimen's own color has changed, and how much color has stained each fiber in the adjacent strip.

Common methods are AATCC 61, an accelerated laundering test in which one cycle is designed to approximate several home washes, and ISO 105-C06, which covers domestic and commercial laundering at different temperatures. Both have several test conditions, so the specification should name the condition as well as the method, ideally one that reflects the care label.

Colorfastness to rubbing (crocking)

Crocking measures how much color rubs off onto another surface. A standard white cloth is rubbed against the fabric a set number of times under controlled pressure, once dry and once wet, and the transferred color is graded. Common methods are AATCC 8, using a crockmeter, and ISO 105-X12. AATCC 116 is a rotary method used for smaller areas such as prints.

Wet crocking results are often lower than dry results, and deep shades such as black, navy, dark red and indigo are where crocking problems usually show up. For dark denim, dark fleece, and anything that will be rubbed against furniture or a lighter garment, crocking is as important as washing.

Colorfastness to light

Light fastness measures fading under exposure to light, usually simulated with a xenon arc lamp. Common methods are AATCC 16 and ISO 105-B02. ISO results are typically rated against a set of blue wool reference fabrics on a scale of 1 to 8, where a higher number means better resistance to fading. Light fastness matters most for outdoor products, curtains and home textiles that sit near windows, swimwear, and items displayed in sunlit retail spaces.

Colorfastness to perspiration

Perspiration tests expose the fabric to artificial acid and alkaline sweat solutions under pressure and heat, then assess color change and staining. Common methods are AATCC 15 and ISO 105-E04. They are relevant for activewear, underwear, T-shirts, shirts and anything worn close to the skin.

Colorfastness to water, chlorine and sea water

Other tests check how color behaves when wet without detergent (AATCC 107, ISO 105-E01), in chlorinated pool water (AATCC 162, ISO 105-E03) and in sea water (AATCC 106, ISO 105-E02). They are mainly requested for swimwear, beach towels and outdoor products. If the care label allows bleach, bleach tests may also apply.

Phenolic yellowing

Phenolic yellowing is not a dye failure, but it is often handled in the same test program. White and pale garments can turn yellow in storage when certain chemicals from packaging materials react with the fabric. ISO 105-X18 assesses the risk. It is worth considering for white and light-colored products that will sit in polybags or cartons for long periods.

How Colorfastness Results Are Graded

Most colorfastness results are expressed on a grey scale from 1 to 5, often in half steps:

Grade 5 means no visible change or no staining.

Grade 4 means slight change or staining.

Grade 3 means noticeable change or staining.

Grades 2 and 1 mean considerable to severe change or staining.

There are two separate grey scales: one for color change in the tested fabric, and one for staining on the adjacent fabric or rubbing cloth. A washing test result therefore usually appears as one color-change grade plus a staining grade for each fiber in the multifiber strip, for example a separate grade for staining on cotton, nylon and polyester. Light fastness under ISO methods uses the separate 1 to 8 blue wool scale described above.

What grade counts as a pass is not fixed by the test method. It is set by the buyer, usually in a brand or retailer quality standard, and it can differ by test, by product type and by shade depth. Many retailers publish their own minimums for suppliers. If you sell through a retailer, use its standard. If you are building your own, decide the minimum grade for each test before sampling, and write it into the specification so the factory and lab test to the same target.

What Causes Poor Colorfastness

Poor results usually trace back to one of a handful of causes. Knowing them makes conversations with a factory more useful than simply reporting a failed grade.

Dye class and fiber. Different dye classes behave differently. Reactive dyes are widely used on cotton and generally give good wash fastness when properly fixed. Vat dyes can give very high fastness and are used where durability matters. Sulphur dyes are common for blacks and some denim and can be weaker on rubbing. Pigment dyeing and pigment printing sit on the fiber surface rather than bonding with it, so they typically fade more and can crock more, which is often the intended washed look. Disperse dyes are used on polyester.

Incomplete wash-off. After reactive dyeing, unfixed dye has to be washed out thoroughly. If the soaping and rinsing after dyeing is cut short, the leftover dye comes out later in the customer's wash. This is one of the most common reasons a fabric bleeds.

Deep and bright shades. Black, navy, deep red, bright turquoise and saturated colors carry more dye and are harder to make fast. A test program usually focuses on the darkest and brightest colors in a range.

Finishing chemicals. Some softeners and finishes can affect rub fastness or shift the shade. A fabric that passed before finishing can behave differently after it.

Dye migration on polyester. On dyed polyester and polyester blends, disperse dye can migrate under heat, for example during print curing or heat transfer, and stain a lighter print or trim. This is why a white print on a red polyester jersey can turn pink.

Mixed components. Threads, labels, zips, drawcords, rib trims and contrast panels are often dyed separately. A garment can fail because a contrast trim bleeds, even when the main fabric passes.

Garment washes. Enzyme, stone, pigment and other garment washes deliberately remove or redistribute color, which changes how the finished garment behaves. Our guide to enzyme wash and garment washing covers those processes.

Colorfastness vs Shade Matching

Colorfastness and shade matching are related but separate. Shade matching asks whether the color on delivery matches the approved standard, within an agreed tolerance and across dye lots. Colorfastness asks whether that color stays put once the product is used. A fabric can be a perfect match and still bleed, or be very fast and still be the wrong shade.

Both should be in the specification. Shade is controlled with a physical color standard, lab dips, a shade tolerance and lot control. Colorfastness is controlled with named tests and minimum grades. Our guide to garment dyed vs piece dyed vs yarn dyed explains lab dips, dye lots and how the dyeing method affects shade consistency.

How to Specify Colorfastness on a Private Label Order

A colorfastness requirement that a factory can work to has five parts. Put them in the tech pack or quality specification, not only in an email.

1. The tests. List which tests apply to this product, for example washing, wet and dry crocking and perspiration for a T-shirt, or washing, crocking and light for a beach towel.

2. The method and condition. Name the method for each test, such as AATCC 61 with a stated test condition, or ISO 105-C06 with a stated procedure, and keep it consistent with the care label.

3. The minimum grades. State the minimum grade for color change and for staining, and for dry and wet crocking separately.

4. Which colors are tested. Usually every colorway, or at least the darkest and brightest shades, and every separately dyed component that touches the main fabric.

5. Who tests and when. Say whether the mill's lab, the factory's lab or an independent third-party lab tests, and at which stage: lab dip, bulk fabric before cutting, finished garment, or more than one.

Our guide to what a tech pack is shows where quality requirements like these sit alongside measurements, materials and construction details.

When to Test: Lab Dip, Bulk Fabric and Finished Goods

A lab dip result is useful for choosing a dye recipe, but it is produced on a small sample under lab conditions. Bulk production can behave differently. The more reliable approach is to test at more than one stage:

At development, on the approved fabric quality and color, to confirm the recipe can meet the target before committing.

On bulk fabric before cutting, using fabric from the actual production dye lot. A failure here can still be corrected by re-washing or re-dyeing fabric, which is far cheaper than fixing finished garments.

On finished garments, where printing, garment washing, trims and finishing are all in place. This catches problems introduced after the fabric stage, such as dye migration into a print.

Colorfastness testing complements visual inspection; it does not replace it. A pre-shipment inspection checks workmanship, measurements and shade against the approved sample, while lab tests check behavior that cannot be seen. Our guide to AQL sampling explains how the visual inspection side works.

Care Labels and Colorfastness

The care label and the colorfastness tests should tell the same story. If the label says machine wash warm, the washing test should be run at a matching condition. If a deep shade is likely to release some color in early washes, a care instruction such as wash with similar colors or wash separately before first use may be appropriate, and it should reflect the test result rather than replace good dyeing. In the US, the FTC Care Labeling Rule requires care instructions on most textile apparel, and those instructions are expected to have a reasonable basis.

Shrinkage is usually tested in the same wash program. If you are already testing washing colorfastness, it is efficient to test dimensional change at the same time; our guide to pre-shrunk cotton explains how factories control shrinkage.

Colorfastness by Product Type

The tests that matter most depend on how the product is used:

T-shirts and jersey basics: washing, wet and dry crocking, perspiration. Our jersey fabric guide covers the fabric itself.

Hoodies and sweatshirts: washing and crocking, especially on dark brushed fleece where rubbing is common. See our guide to French terry vs fleece.

Activewear: perspiration, washing and crocking, plus light for outdoor ranges.

Swimwear: chlorinated water, sea water, light and perspiration.

Towels: washing and crocking, particularly for dark and bright towels that will be washed often and at higher temperatures, and chlorine or bleach where relevant.

Bedding and home textiles: washing and crocking; light for curtains and items near windows.

Baby and children's clothing: washing, crocking, perspiration and, often, saliva fastness under some standards, alongside chemical safety requirements such as those covered by OEKO-TEX certification.

Colorfastness and Production in Turkey

Turkey has a large dyeing, finishing and garment manufacturing base, and colorfastness testing to AATCC and ISO 105 methods is a routine request in textile supply chains serving US and European brands. Which tests a particular factory or partner dye house runs in its own lab, which it sends to a third-party lab, and what testing adds to cost and lead time vary by factory and product, so they should be confirmed at the quote stage rather than assumed.

SourceBridge responds to a textile brief within 24 hours with options from 2–3 pre-vetted Turkish factories. The published starting point for textiles is 300 units per style. Samples typically take 7–14 days, plus 5–7 days for international courier, and production typically runs 4–8 weeks depending on product complexity, with a pre-shipment inspection against the approved sample before goods leave the factory. Including your colorfastness tests and minimum grades in the brief means they can be quoted and planned from the start. Our guides on how to find a clothing manufacturer and clothing manufacturers for startups cover the steps around the specification.

FAQ: Colorfastness

What is colorfastness?

Colorfastness is a fabric's resistance to losing or transferring color when it is washed, rubbed, exposed to light, wet, or exposed to sweat. Good colorfastness means little fading and little staining of other materials.

What does color fastness mean in clothing?

It means the garment keeps its color in normal use and does not bleed onto other clothes, skin or furniture. It is checked with standard laboratory tests rather than by eye.

How is colorfastness tested?

A fabric specimen is washed, rubbed, exposed to light or treated with test solutions under controlled conditions, following methods such as AATCC 61, AATCC 8 or ISO 105-C06. The color change and any staining are then graded against grey scales.

What is a good colorfastness grade?

Grades run from 1, severe change or staining, to 5, no change or staining. There is no single pass mark in the test methods; the minimum is set by the buyer's or retailer's quality standard and can differ by test and shade. Agree it before sampling.

What is crocking in fabric?

Crocking is color rubbing off a fabric onto another surface. It is tested dry and wet with a crockmeter, for example under AATCC 8 or ISO 105-X12. Dark shades and denim are most prone to it.

Why do clothes bleed color in the wash?

Usually because dye that was not fully fixed or washed out during production comes out in the customer's wash. Deep shades, certain dye classes and shortened wash-off after dyeing make bleeding more likely.

What is the difference between colorfastness and shade matching?

Shade matching checks that the delivered color matches the approved standard. Colorfastness checks that the color stays in place during use. An order needs both, specified separately.

Should I test colorfastness on every color?

Ideally yes, because each color uses a different dye recipe. At minimum, test the darkest and brightest shades and any separately dyed trims or panels, on bulk fabric from the production dye lot.

What Is Colorfastness? Fabric Color Fastness Testing Explained