Rebar Calculator — cutting, weight, spacing, and costs

Design bar schedules with spacing, offsets, laps, hooks, and cover allowances, easily on drawings. Compute counts for slabs, beams, columns, and footings with bar presets, including stirrups automatically. Switch metric or imperial units with regional bar size standards. Export results to CSV and PDF for records. Fast, accurate, field‑ready outputs for builders and estimators.

Global Settings
Used to derive theoretical weight. Default is 7850 kg/m³.
Switch between price per kilogram or per length in Global Settings.
Quick Bar Count (spacing) Helper
m
m
m
n = ⌊(run − 2·cover)/spacing⌋ + 1
Cutting List
# Mark Shape Qty Diameter Run length Hook A Hook B Lap Waste Bar length Weight/bar Total weight Cost Notes
Totals 0 0 0
Hook uses multiplier ×db (bar diameter). Defaults: 90°=12db, 135°=9db (adjust per local code). Lap also in ×db, applied once per bar.
Stock-Length Cut Optimization
m
Typical: 12 m (or 40 ft).
m
Allowance added between pieces on the same stock.
m
Remainders smaller than this are treated as waste.
Run optimization to see the cutting plan.
Stock # Pieces (sequence) Used length Waste Yield
Formulas Used
  • Weight per meter (kg/m): w = (π·d²/4)·ρ with d in meters and steel density ρ in kg/m³.
  • With ρ ≈ 7850 and d in millimeters: w ≈ 0.006165 · d2 (kg/m).
  • Bar length: L = run + hookA + hookB + lap + waste.
  • Hooks/Laps: input as multiples of bar diameter (db); e.g., 90° hook ≈ 12·db, 135° hook ≈ 9·db.
  • Quick Count for spacing: n = ⌊(run − 2·cover)/spacing⌋ + 1.

These are typical industry formulas; verify local code requirements and project specifications.

How to Use
  1. Choose unit system and pricing basis; optionally set density and grade.
  2. Use Quick Bar Count to calculate quantity from run, cover, and spacing.
  3. Build your cutting list: add rows and enter quantity, mark, run length, and diameter.
  4. Add hook and lap multipliers in ×db; add extra waste if needed.
  5. Open Stock-Length Cut Optimization, set stock length, kerf, remainder, then run.

Tips: switch units at any time; all values are recalculated automatically.

Example Cutting List (sample)
MarkShapeQtyDiameterRunHook AHook BLapWasteNotes
B1Straight2016 mm5.8 m12×db12×db00.05 mMain slab bars
B2L‑hook1212 mm2.6 m12×db000.02 mBeam starters
B3Stirrup4010 mm1.0 m9×db9×db00.01 mClosed ties
FAQs

Switch between metric and imperial. Inputs and outputs update instantly, including diameter lists, units, and totals.

Weight per meter is derived from bar cross‑sectional area and steel density. For convenience, the constant 0.006165·d² (d in mm) is used widely.

Defaults are 90°≈12db and 135°≈9db, but always confirm with local codes, drawings, and engineer instructions for development and anchorage lengths.

Yes. Toggle the pricing basis in Global Settings, then enter your unit price accordingly. Costs update for each line and overall totals.

It shows the count and can append a new cutting-list line with the computed quantity and selected diameter if you choose to import.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.