Press Brake Tonnage Chart by Material & Thickness
This press brake tonnage chart gives air-bending force estimates by material thickness, V-die opening and reference material. Use the metric table for metric tonnes per metre and the imperial table for US tons per foot. The values are planning references for 90-degree air bends - always verify the actual alloy, machine, holder and tooling ratings before production.
Need an Exact Bend Length?
Use the interactive calculator when the bend is not exactly one metre or one foot. It reports linear load, total US tons, metric tonnes, kN, estimated radius and minimum flange.
Open the Press Brake Tonnage CalculatorPress Brake Tonnage Chart Assumptions
- 90-degree air bending with centred, symmetrical loading
- Mild-steel baseline tensile strength of approximately 60,000 psi
- Mate reference material factors: aluminum 0.5, mild steel 1.0 and stainless steel 1.5
- The exact V opening listed in each row
- No added production margin or correction for a specific alloy certificate
The selected V openings are common starting relationships, not universal recommendations. The metric chart uses about 6 times thickness for 1 to 2 mm sheet, 8 times for 3 to 8 mm and 10 times for 10 to 12 mm. The imperial chart uses common openings that closely follow manufacturer force charts. If your available opening is different, recalculate rather than reading across the same row.
Metric Press Brake Tonnage Chart
Values below are metric tonnes per metre of bend. To estimate total metric tonnes, multiply the chart value by bend length in metres.
| Thickness | V opening used | Aluminum reference | Mild steel reference | Stainless reference |
|---|---|---|---|---|
| 1.0 mm | 6 mm | 5.6 t/m | 11.2 t/m | 16.8 t/m |
| 1.5 mm | 9 mm | 8.4 t/m | 16.8 t/m | 25.3 t/m |
| 2.0 mm | 12 mm | 11.2 t/m | 22.5 t/m | 33.7 t/m |
| 3.0 mm | 24 mm | 12.6 t/m | 25.3 t/m | 37.9 t/m |
| 4.0 mm | 32 mm | 16.8 t/m | 33.7 t/m | 50.5 t/m |
| 5.0 mm | 40 mm | 21.1 t/m | 42.1 t/m | 63.2 t/m |
| 6.0 mm | 48 mm | 25.3 t/m | 50.5 t/m | 75.8 t/m |
| 8.0 mm | 64 mm | 33.7 t/m | 67.4 t/m | 101.1 t/m |
| 10.0 mm | 100 mm | 33.7 t/m | 67.4 t/m | 101.1 t/m |
| 12.0 mm | 120 mm | 40.4 t/m | 80.9 t/m | 121.3 t/m |
Why are the 8 mm and 10 mm mild-steel values the same? The 8 mm row uses an 8× opening while the 10 mm row uses a wider 10× opening. The increased opening offsets part of the force increase. This is exactly why a chart without its V-opening column can be misleading.
Imperial Press Brake Tonnage Chart
Values below are US short tons per foot of bend. Multiply by bend length in feet to estimate total US tons.
| Gauge / thickness | Decimal thickness | V opening used | Aluminum | Mild steel | Stainless |
|---|---|---|---|---|---|
| 20 ga | 0.036 in | 0.250 in | 1.5 tons/ft | 3.0 tons/ft | 4.5 tons/ft |
| 18 ga | 0.048 in | 0.375 in | 1.8 tons/ft | 3.5 tons/ft | 5.3 tons/ft |
| 16 ga | 0.060 in | 0.500 in | 2.1 tons/ft | 4.1 tons/ft | 6.2 tons/ft |
| 14 ga | 0.075 in | 0.625 in | 2.6 tons/ft | 5.2 tons/ft | 7.8 tons/ft |
| 12 ga | 0.105 in | 0.750 in | 4.2 tons/ft | 8.5 tons/ft | 12.7 tons/ft |
| 10 ga | 0.135 in | 1.000 in | 5.2 tons/ft | 10.5 tons/ft | 15.7 tons/ft |
| 3/16 in | 0.188 in | 1.500 in | 6.8 tons/ft | 13.5 tons/ft | 20.3 tons/ft |
| 1/4 in | 0.250 in | 2.000 in | 9.0 tons/ft | 18.0 tons/ft | 27.0 tons/ft |
| 5/16 in | 0.313 in | 2.500 in | 11.3 tons/ft | 22.5 tons/ft | 33.8 tons/ft |
| 3/8 in | 0.375 in | 3.000 in | 13.5 tons/ft | 27.0 tons/ft | 40.4 tons/ft |
| 1/2 in | 0.500 in | 4.000 in | 18.0 tons/ft | 35.9 tons/ft | 53.9 tons/ft |
The mild-steel values align closely with the Mate and Wilson Tool air-bending charts; small differences can result from rounding. Gauge thickness varies by material system, so always use the measured decimal thickness for calculations.
Press Brake Tonnage Formula
Mate publishes the following imperial relationship for a 60,000 psi mild-steel baseline:
Thickness and V opening are entered in inches. Multiply the result by bend length in feet for total US tons. For other known tensile strengths, a more specific factor should be based on the actual material data rather than assuming every aluminum or stainless grade behaves identically.
How Material Changes the Chart Value
| Reference material | Mate planning factor | Use the factor when | Do not assume |
|---|---|---|---|
| Aluminum reference | 0.5 | A preliminary estimate is needed and the exact alloy factor is unavailable. | That soft aluminum and heat-treated 6061-T6 need the same radius or correction. |
| Mild steel, 60,000 psi | 1.0 | The material matches the chart's baseline strength. | That every structural or high-strength steel is a 1.0 factor. |
| Stainless reference | 1.5 | A conservative planning estimate is required before grade-specific review. | That every stainless grade has identical tensile strength or springback. |
How V Opening Changes Required Force
The V opening is in the denominator of the force formula. With material, thickness and bend length unchanged, a wider opening reduces estimated air-bending force. It also produces a larger natural inside radius and requires a longer supported flange. Do not widen the opening to solve a capacity problem until the radius, flange and drawing requirements are checked.
Use the V-die opening guide and the bend-radius and springback guide before finalizing the opening.
How to Use the Tonnage Charts
- Confirm air bending. Stop if the job uses bottoming, coining, hemming or special forming.
- Measure the material. Use actual thickness and verify grade, temper and tensile strength.
- Find the exact V opening. Do not use a row calculated for a different die opening.
- Read the correct linear-load column. Use t/m for metric or US tons/ft for imperial.
- Multiply by bend length. Convert length to metres or feet before calculating total load.
- Verify every component. Compare both total load and linear load with the press brake, holder, punch and die ratings.
- Follow the approved setup procedure. Confirm centring, sectional-tool limits, crowning and a controlled test bend.
Worked Tonnage Examples
Metric example: 3 mm mild steel over a 24 mm V opening
The chart gives approximately 25.3 metric tonnes per metre. For a 1.5 m bend:
The equivalent is about 41.8 US tons. Confirm the exact result with the interactive calculator and manufacturer chart.
Imperial example: 1/4 in mild steel over a 2 in V opening
The chart gives approximately 18.0 US tons per foot. For a 6 ft bend:
Changing the material to stainless
Using Mate's 1.5 reference factor, the same 1/4 in by 6 ft bend estimates to 162 US tons. That multiplication is only a planning reference; the exact stainless grade and approved opening can change the result.
Linear Load vs Total Machine Tonnage
A press brake may have enough total tonnage but still be unsuitable for a concentrated bend. Tooling is often rated per metre or per foot, and machines may impose minimum tool lengths or limits for short, off-centre and sectional loading. Check both numbers:
- Linear load: force per metre or per foot applied to the tooling.
- Total load: linear load multiplied by the full bend length.
- Load distribution: where that force sits across the bed and ram.
Continue the Press Brake Learning Path
Press Brake Tooling to Compare
Always verify the tooling style, opening, angle, radius, length and maximum linear load against the calculated job.
2017 Two-V Die, 60°
Amada-style die with 16 mm and 20 mm openings and a listed 60 T/m maximum.
From $241 CAD
View Two-V Die
2081 Single-V Die, 45°
Amada-style die with a listed 40 mm V opening and 100 T/m maximum.
From $580 CAD
View 40 mm V Die
1011 Straight Punch, 88°
Amada/Promecam-style punch with a listed 0.8 mm tip radius and 100 T/m maximum.
From $202 CAD
View 88° PunchSend the machine and holder model, material grade, measured thickness, bend length, V opening, angle and part drawing.
Request a Tooling Review or Quote
Press Brake Tonnage Chart FAQ
How much tonnage is needed to bend 1/4 inch steel?
Using a 2 inch V opening and a 60,000 psi mild-steel baseline, the estimate is about 18 US tons per foot. Multiply by the actual bend length, then verify machine and tooling ratings.
Why does stainless require more press brake tonnage?
Stainless references commonly use a higher material factor because of higher strength. Mate's general chart uses 1.5 times the mild-steel result, but grade-specific data is more accurate.
Can the chart be used for aluminum?
It provides a 0.5 reference factor. Aluminum alloy and temper strongly affect bendability and springback, so verify the exact material before production.
Does doubling thickness double tonnage?
No, not when V opening remains unchanged. Thickness is squared in the air-bending formula, so doubling thickness would quadruple the estimated linear load. If the V opening is also increased, the final change will be smaller.
Can I use this chart for bottoming or coining?
No. Cincinnati reports that bottoming and coining can require several times normal air-bend tonnage. Use the process-specific manufacturer data.
Manufacturer References
- Mate Precision air-bending force chart - formula, material factors, flange and radius references.
- Wilson Tool air-bending force chart - thickness, opening, force and minimum-flange guidance.
- Cincinnati tonnage calculator - calculation scope and air-bending limitations.
- Cincinnati press brake capacities guide - mild-steel baseline, opening guidance and machine-load considerations.
Continue learning: Visit the Education & Product Guides hub, identify your press brake tooling style, or browse press brake tooling.
Flat-pattern planning: Continue with the press brake bend allowance, K-factor and bend deduction guide.