Lab dip approval is the stage where a dyed fabric swatch is confirmed against your color standard before bulk fabric production begins — skipping or rushing it is one of the leading causes of bulk color disputes.
Provide a Pantone TCX or TPG reference (or a physical swatch) and specify the light source for evaluation; vague color references lead to repeated rejection rounds.
Black, nude, grey, and navy are high-risk colors that typically require closer review and clearer directional feedback during lab dip approval.
Bulk color approval (confirming the actual bulk fabric against the approved lab dip before cutting) is a separate, often overlooked step that protects against dye-batch variation.
Color is one of the most common sources of dispute in bulk apparel orders — and most of those disputes are preventable. The issue rarely starts at bulk production. It usually starts earlier, at the lab dip approval stage, when the color standard was unclear, feedback was too vague to act on, or the approved swatch was never properly archived.
For brands placing custom apparel orders, understanding the lab dip process and what comes after it is part of protecting the product before a single garment is cut. This guide walks through the full color approval chain — from submitting a color standard to confirming bulk fabric — with the practical steps brand buyers need at each stage.
What Lab Dip Approval Means in a Custom Apparel Order
A lab dip is a small fabric swatch dyed by the factory or dye house to match a color standard provided by the buyer. It is submitted for approval before the bulk fabric run begins. The purpose is straightforward: confirm that the color the factory is planning to use actually matches your brand's reference, on the specific fabric the garment will be made from.
This last point matters more than most buyers realize. Dye behavior varies significantly by fabric type. The same Pantone code applied to a cotton jersey, a polyester interlock, and a nylon spandex blend will produce three noticeably different results. Lab dip approval is the step where that variation is caught and corrected before it becomes a large-scale problem.
Lab dip approval covers solid-dyed fabric. For orders involving print patterns or yarn-dyed jacquard, a different confirmation step applies — the strike-off. The table below outlines the key differences:
Feature
Lab Dip
Strike-Off
Applies to
Solid-dyed fabric
Printed or yarn-dyed fabric
What it confirms
Dye color vs. brand standard
Pattern, placement, and color impression
Who initiates
Factory / dye house
Factory / print house
When it happens
Before bulk fabric dyeing
Before bulk printing or weaving
Common example
Navy hoodie — Pantone TCX match
Allover-print leggings — pattern repeat check
For brands ordering solid-color hoodies, tees, or leggings, lab dip is the relevant process. Strike-offs apply where print or pattern consistency needs visual confirmation before full production runs; this is especially relevant when brands are comparing garment print methods before bulk approval.
In the overall sampling flow, lab dip approval sits before fabric production and well before any garment construction begins. For brands managing multiple colorways in a single order, it means running approval on each color separately — a step that benefits from a clear internal deadline to avoid compressing the production schedule later.
How to Provide a Color Standard Your Factory Can Work With
The quality of a lab dip submission starts with the color reference the brand provides. Factories work most accurately when they have a specific, physical or standardized reference to match against — not a description, a digital screenshot, or a general color name.
The two most common formats are:
Pantone TCX (Textile Cotton eXtended): Used for cotton and other natural-fiber fabrics. This is the standard for most woven and knit garments.
Pantone TPG (Textile Paper Green): Used where a physical swatch is not available; commonly referenced for prints and surface applications.
Physical fabric swatch: A cut from an existing garment or a previously approved fabric. This is often more accurate than Pantone codes for colors that are difficult to replicate from a reference number alone.
If you are providing a Pantone code, confirm it comes from the current season's guide rather than an older edition — Pantone periodically updates its libraries and color IDs can shift between versions.
Not all colors carry the same risk. Some are consistently harder to match across different fiber types and dye lots. The table below covers the color categories that most often require additional attention during lab dip approval, including considerations relevant to bulk hoodies and other common OEM categories:
Color Type
Why It's Difficult
What to Flag to Your Factory
Black
"Flares" under UV or sunlight — appears different indoors vs. outdoors
Specify light source for evaluation; confirm no blue or green cast
Nude / Beige
Shifts noticeably across different fiber types (cotton vs. nylon vs. modal)
Send physical reference swatch, not just Pantone code
Grey
Appears warmer or cooler depending on fiber content and dye lot
Request multiple shade options; specify warm or cool direction
Navy
Easy to drift into royal blue or very dark grey under some lighting
Confirm evaluation under D65 daylight; common in hoodies and polo shirts
Off-white
Inconsistent between fabric batches; can appear yellow or cool grey
Provide clear direction on warmth; flag if matching multiple components
High-risk colors often require more lab dip rounds. Building extra approval time into the production schedule for these categories is a practical way to avoid timeline pressure downstream.
One factor that is easy to overlook: the lighting condition under which a lab dip is evaluated. A color that reads as approved under fluorescent office lighting may look noticeably different under D65 daylight simulation or in natural sunlight. Professional factories evaluate lab dips under standardized light sources. If your internal approval process uses standard office lighting, flag this to the factory so you are both evaluating under comparable conditions.
Reading a Lab Dip: How to Evaluate Options and Give Clear Feedback
Factories typically submit multiple shade options per lab dip round — commonly labeled A, B, and C — representing their closest attempts to the brand's standard. The buyer's role is to identify the option that is closest to the target and provide clear feedback on whether it is approved or what direction the next round should take.
Multiple lab dip options evaluated under D65 daylight lighting to identify the closest match to the brand's color standard
When evaluating options, consider:
Hue direction: Is the sample drifting warm (yellow/red) or cool (blue/green) relative to the standard?
Lightness: Is the sample too light or too dark, regardless of hue?
Fabric behavior: Does the color look different dry versus during evaluation — some dyes shift as the fabric dries after finishing?
On the question of color tolerance: industry practice for apparel uses Delta E (ΔE) measurements to quantify the difference between a lab dip and the approved standard. A lower ΔE indicates a closer match. The specific tolerance that a brand considers acceptable varies by category and end use — tighter for fashion items where color is a brand signature, looser for workwear or casual basics. Your factory should be able to confirm what tolerance they are working to. For reference on textile testing standards, ASTM Textile Standards provides access to the textile testing framework commonly referenced across apparel manufacturing and quality control programs.
The most common feedback mistake buyers make is marking a lab dip as "rejected" without direction. From the factory's perspective, "rejected" without a correction note can mean starting over without clear guidance, resulting in another round that misses the target in the same direction. Useful feedback sounds like:
"Option B is closest. Shift slightly cooler and reduce lightness by a small amount."
"All options are too warm. Please move toward a cooler, bluer tone."
"Option A is approved. Please archive and use as the bulk standard."
For printed T-shirts and other items where body color and print color need to coordinate, it is worth confirming lab dip approval for the base fabric before finalizing the print color palette — base color shifts can affect how the overall design reads.
Once a lab dip is approved: both sides should retain a physical swatch labeled with the style, colorway, and approval date. This becomes the reference for the next stage.
Bulk Color Approval: The Stage Most Brands Overlook
Lab dip approval is not the end of the color management process. It is the first gate. The second — and frequently skipped — gate is bulk color approval (sometimes called bulk fabric approval or pre-production color sign-off).
After the lab dip is approved and bulk fabric dyeing begins, the factory produces the actual fabric in the quantities required for production. That bulk fabric should be confirmed against the approved lab dip swatch before cutting begins. This is the bulk color approval step.
Why is this step necessary if the lab dip was already approved? A few common reasons:
Dye batch variation: Bulk fabric is often dyed across multiple batches. Each batch can produce a slightly different shade. Without a pre-cut check, shade variation across a single order's fabric panels may not be caught until garments are partially assembled.
Fiber lot differences: If the factory sources fabric from multiple rolls or batches, even minor differences in the fiber's preparation can affect how it takes the dye.
Production conditions: Temperature, dyeing duration, and post-finishing processes can all affect the final color, and they are harder to control at bulk scale than in the lab.
For brands where color consistency is part of the brand identity — or where a style is ordered in multiple colorways that need to coordinate — requesting a bulk fabric approval step before cutting is a reasonable ask. It adds a small amount of time to the timeline but significantly reduces the risk of discovering shade variation after production is complete.
For more context on how this fits into the broader pre-production confirmation process, the garment sampling process guide covers where color approval sits relative to other approval stages.
At Runtang, bulk fabric goes through an in-house quality check at the dyeing and finishing stage before it moves to cutting. For color-sensitive orders, we recommend brands flag the specific colorways that need closest attention during this stage — particularly for deep tones, neutrals, and any color being matched across multiple product types.
Common Lab Dip Approval Issues and How to Avoid Them
Most lab dip problems are predictable. The same issues appear across orders, categories, and factory relationships. The table below summarizes the most frequent causes and what buyers can do to prevent them:
Issue
Where It Usually Starts
How to Prevent It
Vague rejection feedback
Buyer side
Note color direction (e.g., "too warm, shift cooler") rather than just "rejected"
Wrong base fabric used for lab dip
Factory side
Confirm the lab dip is done on the same fabric construction and weight as the bulk order
Approval with no physical archive
Both sides
Retain the approved swatch with reference number; share one copy with factory
Late approval compressing production timeline
Buyer side
Set internal approval deadlines tied to the production calendar, not the delivery date
Bulk fabric dyed in different batches without re-check
Factory side
Request a pre-production confirmation against the archived approved swatch before bulk cutting
Many of these issues compound each other. A vague color standard leads to more rounds; more rounds lead to timeline pressure; timeline pressure leads to approving a lab dip that is close enough rather than correct. Starting with a clear reference and setting internal approval deadlines breaks this cycle.
One process note worth establishing early: keep a physical archive of every approved lab dip. A labeled swatch stored in a file — with the style name, season, colorway, and approval date — takes almost no effort to maintain and eliminates the most common source of post-production color disputes. When a buyer and factory both have the same physical reference, the conversation shifts from "who is right" to "where did the deviation occur."
FAQ
Do I need to provide a Pantone number, or can I send a fabric swatch instead?
Both are valid, and the best choice depends on the color. For standard colors, a Pantone TCX reference is clear and unambiguous. For colors that are difficult to describe — particularly neutrals, dusty tones, or colors that need to match an existing product — a physical fabric swatch is often more accurate. When in doubt, provide both.
How many rounds of lab dip revision are normal before approval?
One to two rounds is common for most standard colors. High-risk colors — black, nude, grey, deep navy — may require an additional round. If you are consistently seeing three or more rounds, the most likely cause is either an unclear color reference or feedback that lacks directional guidance. Both are fixable on the buyer's side.
What should I do if the bulk fabric doesn't match the approved lab dip?
First, compare the bulk fabric directly against the archived approved swatch under consistent lighting. If there is a visible difference, raise it before cutting begins — this is the moment when correction is still possible. Document the deviation with photos and measurements if available. Once cutting has started, options become significantly more limited. This is why requesting a pre-cut bulk color check is worth building into the approval workflow.
Working with Runtang on Color-Sensitive Orders
Color consistency in bulk production depends on a clear process at every stage — from the reference you provide to the fabric check before cutting. If you have a specific colorway in mind or are sourcing an order where shade accuracy matters, share your color standard or a reference swatch and we will advise on what to expect at the lab dip stage before sampling begins.
