PE Bag Thickness Guide: Microns, Mil & Gauge Explained

📅 June 21, 2026 • 8 min read • By Pebag Factory

If you're importing PE plastic bags from China, one of the most confusing things is thickness measurement. Chinese factories use "丝" (si), US buyers use "mil" or "gauge", and Europeans use "microns". Which one should you use? And what thickness do you actually need?

This guide covers everything you need to know about PE bag thickness — with a handy conversion chart and recommendations for different applications.

What is PE Bag Thickness?

PE (polyethylene) bag thickness refers to how thick the plastic film is. It directly affects the bag's strength, durability, cost, and suitability for different products. Thicker bags are stronger but more expensive. Thinner bags save money but may not protect your products adequately.

Thickness Units: The Complete Conversion Chart

Different countries use different units. Here's how they compare:

丝 (Si)Micron (μm)MilGaugemm
1 丝10 μm0.39 mil394 gauge0.01mm
2 丝20 μm0.79 mil787 gauge0.02mm
3 丝30 μm1.18 mil1181 gauge0.03mm
5 丝50 μm1.97 mil1969 gauge0.05mm
8 丝80 μm3.15 mil3150 gauge0.08mm
10 丝100 μm3.94 mil3937 gauge0.10mm
15 丝150 μm5.91 mil5906 gauge0.15mm
💡 Quick Rule: 1 丝 = 10 microns = 0.01mm. To convert 丝 to mil, multiply by 0.394. Most common PE bags use 3-5 丝 (0.03-0.05mm).

What Thickness Do You Need? By Application

📦 Lightweight Items (1-3 丝 / 0.01-0.03mm)

  • Garment bags — 1-2 丝 for dry cleaning and apparel
  • Grocery/shopping bags — 1.5-2.5 丝
  • Produce bags — 1-1.5 丝 for fruits and vegetables
  • General merchandise — 2-3 丝 for light products

📦 Medium Items (3-5 丝 / 0.03-0.05mm)

  • Food packaging — 3-4 丝 for snacks, dry foods, frozen items
  • Hardware parts — 4-5 丝 for screws, nuts, small components
  • Electronics accessories — 3-4 丝 for phone cases, cables
  • Sample bags — 3 丝 for product samples and promotional items

📦 Heavy Items (5-10 丝 / 0.05-0.10mm)

  • Industrial parts — 6-8 丝 for heavy components
  • Chemicals/ powders — 8-10 丝 for thick protection
  • Shipping packaging — 5-8 丝 for mail order bags
💡 Cost Tip: Doubling the thickness roughly doubles the material cost. For example, a 5 丝 bag costs about 70% more than a 3 丝 bag of the same size. Choose the thinnest bag that still provides adequate protection for your product.

FOB Price Reference by Thickness

Based on our factory pricing, here's what different thicknesses cost for a standard 200×250mm (8×10") PE flat bag:

ThicknessWeight per bagFOB Price (per bag, bulk)
2 丝 (0.02mm)0.59g$0.003
3 丝 (0.03mm)0.88g$0.005
5 丝 (0.05mm)1.47g$0.008
8 丝 (0.08mm)2.35g$0.013

Want an exact price for your specific size and thickness? Use our Instant Price Estimator for a precise FOB quote.

Common Questions About PE Bag Thickness

Is thicker always better?

No. Thicker bags cost more and generate more plastic waste. Choose the thickness that matches your product's weight and protection needs. Over-packaging wastes money and material.

What thickness do most e-commerce businesses use?

Most e-commerce and retail packaging uses 2-4 丝 (0.02-0.04mm) PE bags. This range offers good protection at an economical price point.

How do I measure bag thickness?

Use a digital micrometer or thickness gauge. Measure the film in multiple spots and average the readings. Film thickness can vary slightly across the bag width.

Can I mix thicknesses in one order?

Yes. We can produce different thicknesses in the same order. Each size/thickness combination is treated as a separate line item. Contact us for a multi-item quote.

Need Help Choosing the Right Thickness?

Not sure what thickness you need? Send us your product details and we'll recommend the optimal bag specification — free of charge.

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