Standard Steel Sheet Sizes & Thicknesses: A Quick Reference

Introduction

When buying steel sheet and plate, it’s important to know the standard sizes available. Choosing standard sizes minimizes cost, reduces waste, and speeds up delivery. This guide covers the most common standard sizes for carbon steel and stainless steel sheet and plate.

Sheet vs Plate: What’s the Difference?

The distinction between “sheet” and “plate” is based on thickness:

Common threshold: Many mills consider material 3.0mm and under as sheet (coil-fed) and above 3.0mm as plate (discrete pieces or heavy coil).

Standard Steel Sheet Sizes (mm & inches)

Metric Standard Sizes (Most Common in China / Asia / Europe)

Cold Rolled Steel Sheet (CR)

Sheet sizes (W × L):

• 1000 × 2000 mm (39.4" × 78.7")
• 1220 × 2440 mm (4’ × 8’) — most common
• 1250 × 2500 mm (49.2" × 98.4")
• 1500 × 3000 mm (59.1" × 118.1")

Common thicknesses (mm): 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 3.0 mm

Hot Rolled Steel Sheet / Plate (HR)

Sheet sizes (W × L):

• 1250 × 2500 mm
• 1500 × 3000 mm
• 1500 × 6000 mm
• 1800 × 6000 mm
• 2000 × 6000 mm
• 2000 × 8000 mm (plate)
• 2200 × 8000 mm (plate)
• 2500 × 10000 mm (heavy plate)

Common thicknesses (mm): 2.0, 2.5, 3.0, 4.0, 5.0, 6.0, 8.0, 10, 12, 14, 16, 18, 20, 22, 25, 30, 35, 40, 45, 50 mm

Thicker plate: 60, 70, 80, 100, 120, 150, 200 mm+

Stainless Steel Sheet

Sheet sizes (W × L):

• 1000 × 2000 mm
• 1220 × 2440 mm (4’ × 8’) — most common
• 1500 × 3000 mm
• 1500 × 6000 mm (plate)

Common thicknesses (mm): 0.4, 0.5, 0.6, 0.8, 1.0, 1.2, 1.5, 2.0, 2.5, 3.0, 4.0, 5.0, 6.0, 8.0, 10 mm

Galvanized Steel Sheet (GI)

Sheet sizes (W × L):

• 1000 × 2000 mm
• 1220 × 2440 mm (4’ × 8')
• 1250 × 2500 mm

Common thicknesses (mm): 0.4, 0.5, 0.6, 0.75, 0.8, 1.0, 1.2, 1.5, 2.0, 2.5, 3.0 mm

Imperial Standard Sizes (US / North America)

Common Sheet Sizes (feet & inches)

• 36" × 96" (3’ × 8')
• 48" × 96" (4’ × 8’) — most common
• 48" × 120" (4’ × 10')
• 60" × 120" (5’ × 10')
• 72" × 240" (6’ × 20’) — for plate

Gauge Thicknesses (US Gauge)

Note: Gauge numbers vary between material types (carbon, galvanized, stainless, aluminum). Always confirm actual thickness in mm or inches.

Standard Coil Widths

Steel is typically produced in coil form first, then cut to sheet lengths or processed further.

Common Coil Widths:

Cold Rolled / Galvanized / Stainless:

• 1000 mm (39.4")
• 1200 mm (47.2")
• 1219 mm / 1220 mm (48") — most common
• 1250 mm (49.2")
• 1500 mm (59.1")
• 1524 mm (60")

Hot Rolled Coil:

• 1250 mm (49.2")
• 1500 mm (59.1")
• 1800 mm (70.9")
• 2000 mm (78.7")
• 2200 mm (86.6")

Coil Weight

• Cold rolled coil: 3–8 tons (typical)
• Hot rolled coil: 10–30 tons (typical)
• Stainless steel coil: 3–10 tons (typical)

Steel Sheet Weight Calculation

Basic Formula:

Weight (kg) = Length (m) × Width (m) × Thickness (mm) × 7.85

Where 7.85 is the density of carbon steel in g/cm³ (or tonnes/m³).

Quick Reference: Weight per m²

For stainless steel, use 8.0 instead of 7.85 (slightly higher density).

Example Calculation:

How much does a 4’×8’ sheet of 2mm steel weigh?

• 1220 mm = 1.22 m
• 2440 mm = 2.44 m
• Area = 1.22 × 2.44 = 2.9768 m²
• Weight = 2.9768 × 2 × 7.85 = 46.7 kg per sheet

Thickness Tolerances

Steel thickness has allowed variation by standard. This is important because “3mm” steel isn’t exactly 3.000 mm.

Typical Thickness Tolerances (reference):

Cold rolled sheet (EN 10051 / ASTM A568):

• ±0.05 mm for thin gauges
• ±0.08 mm for 1–2 mm
• ±0.10 mm for 2–3 mm

Hot rolled plate (EN 10029 / ASTM A6):

• ±0.3 mm for 5–10 mm
• ±0.5 mm for 10–25 mm
• ±0.8 mm for 25–50 mm
• ±1.0% of thickness for heavy plate

Stainless steel 2B sheet:

• Similar to cold rolled carbon steel
• Typically ±5–8% of thickness

Important: Thickness is usually measured at a specific distance from the edge, not at the absolute edge where it can be thinner.

Length and Width Tolerances

Sheet length & width tolerance:

• Cold rolled: typically 0 / +5 mm (can’t be undersize)
• Hot rolled: typically 0 / +10 mm
• Stainless: 0 / +5 mm

Flatness:

• Cold rolled: very flat (≤3–5 mm/m)
• Hot rolled plate: moderate (≤8–15 mm/m)
• Stainless 2B: very flat

How to Order Steel Sheet / Plate

When placing an order, specify:

1. Grade & Standard — e.g., “Q235B per GB/T 700” or “304 stainless per ASTM A240”
2. Product form — sheet, plate, or coil
3. Surface / finish — mill finish, 2B, BA, galvanized, pickled, etc.
4. Thickness — in mm (specify gauge only if you know the standard)
5. Width — in mm or feet
6. Length — in mm or feet (or “coil” for coil supply)
7. Quantity — number of sheets, tons, or lineal meters
8. Tolerance class — if special accuracy is needed
9. Certification — MTC required? 3.1 or 3.2?
10. Additional processing — cutting, slitting, bending, punching, etc.

Choosing the Right Thickness

Common Applications by Thickness:

How to Determine Required Thickness:

1. Engineering calculation — calculate based on load, span, and allowable stress
2. Reference existing designs — use proven dimensions from similar applications
3. Consult with an engineer — for critical or safety-related applications
4. Consider corrosion allowance — add extra thickness for corrosion over service life
5. Factor in stiffness — sometimes stiffness (not strength) governs thickness
6. Use standard thicknesses — non-standard thicknesses cost more and have longer lead times

Standard vs Custom Sizes

Standard Sizes

• ✅ Lowest cost
• ✅ Fastest delivery
• ✅ Best availability
• ✅ Multiple suppliers to choose from
• ❌ May not fit perfectly (some waste from cutting)

Custom Sizes (cut to order)

• ✅ Exact dimensions for your application
• ✅ Less waste (but higher cutting cost)
• ✅ Can optimize material usage
• ❌ More expensive
• ❌ Longer lead time
• ❌ Minimum order quantity may apply

Rule of thumb: Use standard sizes whenever possible. Order custom-cut only if the waste savings justify the extra cost.

Tips for Buying Sheet and Plate

1. Specify thickness in mm, not gauge — gauge numbers are inconsistent between standards
2. Check what thickness you actually get — steel is usually supplied at or just above the nominal thickness (on the plus side)
3. Buy from coil for small quantities — many suppliers can cut-to-length from coil for fast delivery
4. Consider weight limits — full sheets can be heavy (a 10mm 4’×8’ plate weighs ~234 kg)
5. Order extra for scrap — account for cutting waste and test coupons (5–10% extra is typical)
6. Confirm surface condition — mill finish, oiled, dry, pickled, etc.
7. Plan for handling — heavy plate requires appropriate lifting equipment

Conclusion

Understanding standard steel sheet and plate sizes helps you make cost-effective purchasing decisions. Sticking to standard sizes and thicknesses minimizes cost, reduces lead time, and ensures availability. When in doubt, specify in millimeters (not gauge) and confirm tolerances with your supplier.

At {{ .Site.Params.companyShortName }}, we supply steel sheet and plate in all standard sizes and can also provide custom cut-to-size service. Contact us for a competitive quote on your sheet and plate requirements.