Software · Quantity Survey & BBS

Bar bending schedule software — IS 2502 BBS online, free

This is free bar bending schedule software that opens in a browser: you enter the footings, columns, beams and slabs shown on a structural drawing, and it returns a complete BBS — shape, diameter, number of bars, cutting length, weight — with the arithmetic done to IS 456, IS 2502, SP 34 and IS 13920. It is written for the people who have to produce and pass a schedule: a site engineer ordering steel, a detailer preparing a cut list for the bar bender, a quantity surveyor billing reinforcement, and the junior engineer who has to check all three.

The distinguishing feature is not the calculation. It is that every row prints the formula that produced it, so nothing has to be taken on trust.

What you can do

Feature	What it does	Export
Member-wise entry	Footing, column, beam and slab forms taking mark, nos, dimensions, clear cover, bar diameters, bar counts and spacings straight off the drawing	Excel · print
Cutting lengths	Straight runs measured outside-to-outside, plus hook allowances, less bend deductions of 1d, 2d and 3d — SP 34 shapes with their code numbers	Excel · print
Formula on every row	The derivation string sits beside the number, so a checker re-does the sum on paper instead of believing a black box	Excel · print
Ld and lap factors	Computed from your steel grade (Fe250–Fe600) and concrete grade (M15–M50), with the deformed-bar and compression increases of IS 456 applied	Excel
Automatic laps	Where a member runs past the 12 m stock bar length, laps are counted and appear as their own measured items	Excel
Seismic hooks	135° stirrup and tie hooks at 10d subject to the 75 mm minimum of IS 13920	Excel · print
Weights	Unit weight of d²/162, row weight, per-member subtotals and a schedule total	Excel · print
Dia-wise summary	A second sheet gathering length, bar count and weight by diameter with SUMIF — the sheet a purchase order is written from	Excel
Basis sheet	A third sheet recording grades, cover, hook and deduction rules, the code clauses used and the drawing reference	Excel
Wastage	A wastage percentage applied to the total, so the ordered tonnage is not the theoretical one	Excel
Live Excel formulas	Unit weight, total length and weight are real formulas in the workbook — change a diameter and Excel recalculates	.xlsx
Hand-off	Push the computed steel into the measurement sheet and on into the BOQ, where it is priced against DSR or SOR rates	BOQ
Optional drawing read	Upload a structural drawing and have dimensions read into the form for you to confirm — the arithmetic never involves AI	—

How it fits Indian reinforcement practice

An Indian BBS lives or dies on four code references, and the tool keeps all four visible rather than hiding them in a constant somewhere. IS 456 governs clear cover, development length and lap length — the lap being the greater of L_d and 30d in tension, 24d in compression. IS 2502 gives the schedule's own format and the standard hook allowances. SP 34 supplies the detailing shapes and the bend deductions that correct outside-to-outside measurement for the fact that steel bends on an arc. IS 13920 adds the 135° hook with its 10d leg and 75 mm floor wherever ductile detailing applies.

Cutting length = Σ straight runs + Σ hook allowances − Σ bend deductions · Weight (kg/m) = d² / 162

Stock length matters too. Steel is supplied in India in 12 m lengths, so any bar longer than that needs a splice; the schedule counts those laps and shows them as their own rows rather than quietly inflating a length. That distinction is what lets a running bill stand up: a checker can see the laps being paid for.

Downstream, the steel weight does not stop at the schedule. Send it to the measurement sheet and it becomes a takeoff line; from there the BOQ prices it against CPWD DSR 2023, a State PWD schedule of rates, or a market rate you have entered — and the same figure carries through into the sanctioned estimate and the RA bill. One tonnage, one origin, checkable end to end.

How to make a bar bending schedule

Open Quantity Survey & BBS and switch to the Bar Bending Schedule section.
Set the basis — steel grade, concrete grade and whether the bars are deformed. This fixes the L_d and lap factors for the whole schedule.
Add a member: choose footing, column, beam or slab and give it a mark (F1, C1, B1, S1) and the number of identical members.
Type the dimensions off the drawing — sizes, height or span, clear cover, main and secondary bar diameters, bar counts, stirrup or tie diameter and spacing.
Optionally upload the drawing and let the reader pre-fill those fields, then check every value against the sheet before you accept it.
Read the formula column on a couple of rows and verify them by hand. If a hook or a deduction is not what your detailer expects, change the input rather than the answer.
Set the wastage percentage and review the dia-wise totals against what you intend to order.
Export the Excel workbook or print the schedule, and push the steel weight into the takeoff and BOQ if you are billing it.

What CivilOS does not do

No structural design or analysis. It will not size a member or select bars from a bending moment. You enter what the structural drawing already specifies.
Four member types only — footing, column, beam and slab. There is no generator for staircases, rafts, shear walls, pile caps or retaining walls; those must be built from the general members or scheduled elsewhere.
No BS 8666 shape codes. The shapes and codes follow Indian SP 34 / IS 2502 practice, not the British schedule format.
No machine output. There is no BVBS or ASA file for driving an automatic cut-and-bend line.
No bar-nesting or splice-stagger optimisation. The schedule does not minimise offcuts or arrange staggered laps for you.
No rebar extraction from a model or DWG. Reinforcement is not read out of a 3D model or a CAD file; drawing reading is an optional aid on dimensions that you confirm.

Where a browser BBS tool fits

Reinforcement scheduling in India is done in three broad ways today. Detailing add-ons that sit on top of a CAD or BIM platform generate schedules directly from a modelled or drawn rebar layout, which is powerful on large repetitive structures where the model is being built anyway. In-house spreadsheet templates are the commonest tool by far: fast, familiar, and as reliable as whoever last edited the formulas. And a good many schedules are still written out by hand on site.

A browser tool fits between the second and the third. It gives the spreadsheet's directness — type the member, read the answer — without the risk that a copied row has quietly lost its formula, and it prints the derivation so a checker is not asked to trust a cell reference. It does not model your rebar, and it will not replace a detailing workflow where the model already exists. For a footing schedule that has to be ordered on Monday, or a beam schedule a junior engineer must be able to defend in front of the client, it is usually enough.

Frequently asked questions

Is this bar bending schedule software really free?
Yes. The BBS tool is free, runs in the browser and needs no installation or licence. The optional drawing-reading assistant uses AI and is subject to fair-use limits, but the schedule itself, including the Excel export, is free to use without it.

Which Indian codes does the schedule follow?
IS 456 for development length, lap length and cover; IS 2502 and SP 34 for bar shapes, hook allowances and bend deductions; and IS 13920 for the 135° seismic stirrup hook of 10d subject to a 75 mm minimum. The basis sheet in the Excel export records which values were used.

Does AI calculate the steel quantities?
No. Every cutting length, weight and total is computed by deterministic code from the IS clauses, and each row prints the formula that produced it. AI is used only, and only if you choose, to read dimensions off an uploaded drawing into the input form — and you confirm every value before it is used.

Which members can I schedule?
Four member types: isolated footings, columns, beams and slabs. Each takes the dimensions, clear cover, bar diameters, bar numbers and spacings that a structural drawing gives you, and produces main bars, distribution bars, ties or stirrups and the laps that follow from the member length.

Can I export the BBS to Excel?
Yes, and it is a formatted workbook rather than a dump. The schedule sheet carries a title block and the grid, the dia-wise summary is linked to it by SUMIF, and unit weight, total length and weight are live formulas — change a bar size and the workbook recalculates in Excel.

Does the software design the reinforcement for me?
No. CivilOS does no structural analysis or design. It does not size a member, choose a bar diameter or work out a spacing from a bending moment. You enter what the structural drawing specifies, and the tool schedules and weighs it.

Can a checker verify a cutting length by hand?
That is the point of the formula column. A row does not just say 1244 mm; it shows the straight runs, the hook allowances added and the bend deductions subtracted, so a junior engineer or a departmental checker can re-do the arithmetic on paper in under a minute.

Make your BBS free → IS 2502 cutting lengths, checkable formulas, Excel export

Draft for checking. Site conditions, splice staggering and the structural designer's notes take precedence. A licensed structural engineer must review and sign off before steel is cut.