What is OZ (Ounces per Square Yard)?

OZ (oz/yd²) stands for ounces per square yard and is the traditional unit of measurement for fabric weight in the United States. It represents the weight of one square yard of fabric measured in ounces and is part of the imperial measurement system.

OZ has been the standard in the American textile industry for decades, particularly for denim, canvas, upholstery fabrics, and workwear. Many US-based fabric mills, retailers, and garment manufacturers continue to specify fabric weights in OZ, making it essential knowledge for anyone working with American fabric suppliers or clients.

Common OZ ranges for popular fabrics:

• Lightweight fabrics (chiffon, voile, gauze): 1-3 OZ
• T-shirt and jersey fabrics: 4-6 OZ
• Lightweight denim: 5-8 OZ
• Standard denim (jeans): 10-13 OZ
• Heavy-weight denim: 14-16+ OZ
• Canvas and workwear: 8-12 OZ
• Upholstery fabrics: 12-20+ OZ

What is GSM (Grams per Square Meter)?

GSM (g/m²) stands for grams per square meter and is the international standard unit for measuring fabric weight. It represents the weight of one square meter of fabric in grams and is part of the metric system used globally.

GSM is the preferred measurement in most countries worldwide, including Europe, Asia, Africa, and Australia. It provides a standardized, precise way to specify fabric weight that’s consistent across international borders. Understanding GSM is crucial for global textile trade and international fabric sourcing.

Common GSM ranges for various fabrics:

• Sheer fabrics: 30-80 GSM
• Lightweight fabrics: 80-150 GSM
• Medium-weight fabrics: 150-250 GSM
• Heavy-weight fabrics: 250-400 GSM
• Very heavy fabrics: 400+ GSM

Quick Conversion: OZ ↔ GSM

• 1 OZ = 33.906 GSM
• 1 GSM = 0.0295 OZ

Conversion Formulas:

• To convert OZ to GSM: GSM = OZ × 33.906
• To convert GSM to OZ: OZ = GSM ÷ 33.906

Use these formulas for manual conversions, or simply use our free converter above for instant, precise results.

Why Use Our OZ to GSM Converter?

• Instant, accurate fabric weight conversions between OZ and GSM
• Mobile-friendly interface that works perfectly on all devices
• Essential for US-based businesses working with international suppliers
• Ideal for textile manufacturers, fashion designers, fabric buyers, and garment merchants
• Saves valuable time compared to manual calculations
• Perfect for converting US fabric specifications to international standards
• Helps prevent costly ordering errors in international fabric purchases
• No registration, no download, completely free to use

Common OZ to GSM Conversions

• 1 OZ = 33.91 GSM (very light voile)
• 2 OZ = 67.81 GSM (lightweight cotton)
• 3 OZ = 101.72 GSM (light jersey, chiffon)
• 4 OZ = 135.62 GSM (T-shirt fabric)
• 5 OZ = 169.53 GSM (standard T-shirt, light denim)
• 6 OZ = 203.44 GSM (premium T-shirt, lightweight denim)
• 8 OZ = 271.25 GSM (medium denim, canvas)
• 10 OZ = 339.06 GSM (standard jeans denim)
• 12 OZ = 407.47 GSM (heavy denim)
• 15 OZ = 508.59 GSM (heavyweight denim, workwear)
• 20 OZ = 678.12 GSM (extra heavy denim, upholstery)

Practical Applications of OZ to GSM Conversion

Converting US Specifications to International Standards: When working with American clients or US fabric specifications, you’ll need to convert OZ measurements to GSM for international suppliers. This ensures accurate communication and prevents ordering the wrong fabric weight from overseas manufacturers.

Denim Manufacturing: The denim industry traditionally uses OZ measurements in the US, but many international denim mills and Asian manufacturers work exclusively in GSM. Converting between these units is essential for maintaining consistency in denim production across different regions.

Importing US Fabrics: When importing fabrics from the United States to countries using the metric system, converting OZ to GSM helps with customs documentation, quality specifications, and communication with local clients who expect GSM measurements.

Technical Specifications: Product developers creating tech packs for international production must provide fabric specifications in GSM, even when the original design uses OZ measurements. Accurate conversion ensures the final product matches the intended design.

Fabric Trading and Distribution: Fabric distributors serving both US and international markets need to provide specifications in both measurement systems. Quick, accurate conversion helps serve diverse customer bases effectively.

Understanding Fabric Weight: OZ vs GSM

Both OZ and GSM measure fabric weight but use different unit systems and reference areas. OZ uses the imperial system and measures weight per square yard, while GSM uses the metric system and measures weight per square meter.

The key difference: A square yard (36″ × 36″) is slightly smaller than a square meter (39.37″ × 39.37″), which is why the conversion factor is 33.906 rather than a simple unit conversion. This accounts for both the weight conversion (ounces to grams) and the area conversion (square yards to square meters).

Why conversion matters: Using the wrong measurement system can lead to significant errors. For example, ordering a “10 OZ” fabric when you meant “10 GSM” would result in receiving fabric that’s over 300 times heavier than intended—a costly mistake that could ruin an entire production run.

Industry trends: While the US textile industry continues to use OZ, there’s a gradual shift toward GSM in international commerce. Many US-based companies now provide dual specifications (e.g., “12 OZ / 407 GSM”) to accommodate both domestic and international clients.

Learn more about units of textile measurement Textile Measurement Units , a trusted universal educational platform All.

Frequently Asked Questions (FAQ)

Q: Why does the US use OZ instead of GSM?

A: The United States predominantly uses the imperial measurement system, which includes ounces and yards. While most of the world has adopted the metric system (GSM), the US textile industry has retained OZ due to historical precedent and established industry standards.

Q: What is a good OZ weight for jeans?

A: Standard jeans typically range from 10-13 OZ (339-441 GSM). Lightweight summer jeans may be 8-10 OZ, while heavyweight or raw denim can be 14-16+ OZ.

Q: How do I measure fabric weight in OZ?

A: Cut a precise square yard (36″ × 36″) of fabric and weigh it in ounces using a scale. The result is the fabric weight in OZ. For smaller samples, you can calculate proportionally or convert from GSM measurements.

Q: Is the conversion the same for all fabric types?

A: Yes! The OZ to GSM conversion formula (1 OZ = 33.906 GSM) is universal and applies to all fabric types including cotton, polyester, denim, silk, wool, canvas, knits, and wovens. The conversion is purely mathematical and doesn’t depend on fabric composition.

Q: Do I need to convert OZ to GSM when ordering from Asian suppliers?

A: Yes, most Asian fabric manufacturers and suppliers work exclusively in GSM. Converting your OZ specifications to GSM ensures clear communication and accurate orders. Many suppliers may not be familiar with OZ measurements.

Q: What’s the difference between fabric weight and fabric thickness?

A: Fabric weight (OZ or GSM) measures mass per area, while thickness measures the physical depth of the fabric. Two fabrics can have the same weight but different thicknesses depending on their density, weave structure, and fiber type. Weight is generally more important for fabric specifications.

Tips for Working with OZ and GSM Measurements

• Always specify the unit: When communicating fabric specifications, always include “OZ” or “GSM” to avoid confusion.
• Double-check conversions: For critical orders, verify your conversions to prevent costly mistakes.
• Keep a conversion chart: Save common conversions for quick reference in your daily work.
• Understand your market: Know whether your clients, suppliers, and partners work in OZ or GSM.
• Request samples: When possible, order fabric samples to physically verify weight before large purchases.
• Consider fabric type: Different fabric constructions (knit vs. woven) can feel different even at the same weight.
• Account for finishing: Fabric finishing processes can affect weight, so specify whether you need greige or finished weight.