Free Bill of Quantities Calculator for Civil Engineering

You can generate a measured Bill of Quantities for a civils assembly right now, free, in the browser. No sign-up, no card, no trial clock. Pick one of six assemblies, enter your geometry or keep the defaults, and the calculator returns a dimensioned drawing, a bill measured in accordance with MMHW, and a per-row audit trail showing where every quantity came from. You can export the result to Excel (watermarked, with the audit trail included). Free output is for research and illustration; it is not warranted for tender or contract use.

If you want the background first, read what a Bill of Quantities is. If you are comparing tools, see Bill of Quantities software. Otherwise, the calculators are below.

The six free calculators

• Manhole: a precast concrete chamber. Measures the rings, the excavation, the base and benching concrete, the reinforcement and the granular surround.
• Headwall: an in-situ concrete headwall at a pipe outfall. Measures the concrete, the formwork, the reinforcement and the dig.
• Gully: a road gully and its connection to the carrier drain. Measures the gully pot, the trench, the bedding and the connection pipe.
• Cantilever retaining wall: a reinforced concrete cantilever wall. Measures the base and stem concrete, the formwork, the reinforcement and the earthworks around it.
• Attenuation tank: a buried stormwater attenuation tank. Measures the excavation, the tank structure, the surround and the backfill.
• End-area earthworks: cut and fill along a chainage line from cross-section areas, the classic end-area method. Measures the cut, the fill, the topsoil strip and the disposal.

The full catalogue of 46 assemblies lives at /calculators; the six above are the free ones.

What is free and what is not

The free tier is the real engine, not a demo with invented numbers. Each free compute gives you the on-screen dimensioned drawing, the MMHW bill with a per-row audit trail, and a watermarked Excel export that keeps the audit trail. The boundaries are these: six assemblies (the other 40 are paid), one standard (MMHW; CESMM4, NRM2 and SMM7 are paid), a watermark on the Excel, and the disclaimer above, which means free output is for research and illustration, not for a live tender.

Paid starts at a £15 7-day pass, or £55/month Solo (£44/month paid annually). That unlocks all 46 assemblies, all four standards, clean Excel, DXF and dimensioned PDF drawings, Word reports and saved projects. Details on the pricing page.

One scope note that applies to both tiers: the engine measures quantities, never rates, and it measures civils assemblies, not a complete project BoQ. Prelims and site-wide items are yours.

The 60-second proof

Open the manhole calculator. It loads with a sensible default: a 1,500 mm internal diameter precast chamber, 3.5 m deep. Leave it, or type in your own chamber size and depth. The engine computes deterministically, so the same inputs always return the same bill, and a 6-character hash cell ties the drawing to the bill. At the default you get a full MMHW bill, including rows like these:

The audit trail alongside the bill shows the derivation for every row: the rule applied and the arithmetic from your stated geometry to the quantity. That is the whole pitch in one screen. You did not trace anything; you stated the chamber size and depth, and every row arrived with its working attached.

Also free inside Claude

The same free tier works inside Claude. Add the CivilQuants connector (the MCP endpoint is https://api.civilquants.com/mcp) and the six free compute tools run in chat with no account: ask Claude to measure a 1,500 mm manhole at 3.5 m and it calls the same engine the browser calculators use, returning the same deterministic bill. Full setup instructions are at /mcp.

FAQ

Is it really free? Yes. Six assemblies render in the browser with no sign-up and no card: the drawing, the MMHW bill with its audit trail, and a watermarked Excel export. There is no trial period to expire.

What's the catch? The Excel export is watermarked, the free tier renders MMHW only, and free output is for research and illustration; it is not warranted for tender or contract use. The paid tiers exist for the other 40 assemblies, the other three standards and the clean exports.

Do I need to install anything? No. The calculators run in the browser. If you use Claude, you can also add the MCP connector and run the same six free tools in chat, again with no account.

Which standards does the free tier render? MMHW, the Method of Measurement for Highway Works. CESMM4, NRM2 and SMM7 are paid-tier standards.

Can I use the free output in a tender? No. Free output is for research and illustration and is not warranted for tender or contract use. For a live job, the £15 7-day pass unlocks the full catalogue, all four standards and clean exports.

Does it price the bill? No. The engine measures quantities only, never rates. It produces the measured rows for civils assemblies; pricing, prelims and site-wide items are yours.

Try it

Pick an assembly and read a real bill in the next minute: the manhole calculator is the fastest proof, or browse all six free assemblies from the catalogue. No sign-up, no card, and the audit trail is on every row.