Almost every dispute over a rebar delivery starts the same way: the figure on the delivery note does not match the weighbridge reading on site. The buyer feels short-changed, the supplier insists the load is correct, and the discussion goes nowhere because no one has agreed on how the weight should be calculated in the first place.

The basis is actually simple. Under SNI, the weight of reinforcing steel depends only on its nominal diameter — not on the brand and not on the surface pattern. This page gives the full weight table and shows how to use it, so you can verify any delivery yourself before signing the paperwork.

The formula SNI uses

Weight is derived from the nominal cross-sectional area multiplied by the density of steel. Simplified, it becomes the single formula used across the industry:

Weight (kg/m) = 0.006165 × d², with d in millimetres.

The standard bar length in Indonesia is 12 metres, so the weight per bar is simply that figure multiplied by twelve. For a 16 mm bar: 0.006165 × 16 × 16 = 1.578 kg per metre, and 1.578 × 12 = 18.94 kg per bar.

Plain and deformed bars weigh the same

This comes up constantly. Plain bar (BjTP) and deformed bar (BjTS) of the same nominal diameter weigh exactly the same, because the ribs are already accounted for within the nominal diameter. The difference between them is bond strength with concrete, not mass. We cover this in detail in our article on plain versus deformed rebar.

SNI rebar weight table

The table below applies that formula across every diameter commonly used on Indonesian projects. The last column makes it easy to convert an order from tonnes into bars.

Diameter Weight per metre (kg) Weight per 12 m bar (kg) Bars per tonne (rounded)
8 mm 0.395 4.73 211
10 mm 0.617 7.40 135
12 mm 0.888 10.65 94
13 mm 1.042 12.50 80
16 mm 1.578 18.94 53
19 mm 2.226 26.71 37
22 mm 2.984 35.81 28
25 mm 3.853 46.24 22
29 mm 5.185 62.22 16
32 mm 6.313 75.76 13
36 mm 7.990 95.88 10
40 mm 9.864 118.37 8

The final column is rounded to the nearest whole bar, so for large orders it is safer to recalculate using the weight per bar rather than the rounded figure.

Worked examples

From weight to number of bars

Suppose the bill of materials calls for 5 tonnes of D16 deformed bar. One D16 bar weighs 18.94 kg, so 5,000 ÷ 18.94 = 263.9 bars, rounded up to 264. Checking backwards, 264 × 18.94 = 5,000.16 kg — effectively exactly five tonnes.

From number of bars to weight

A delivery contains 120 bars of D13 and 300 bars of D10. That is 120 × 12.50 = 1,500 kg plus 300 × 7.40 = 2,220 kg, for a total of 3,720 kg. If the weighbridge reads well below that, ask questions before the load is unpacked.

Why one size up costs so much more

Because diameter is squared, moving up a size raises weight far faster than most people expect. A D25 bar weighs 3.7 times as much as a D13 bar, not roughly twice as much as the diameters alone would suggest. This matters for budgeting: a design change from D13 to D25 multiplies the tonnage you have to buy.

Common mistakes when using a weight table

  • Assuming a small shortfall must be acceptable. SNI does allow a weight tolerance, and it differs by diameter range. The question is whether the deviation falls inside the official tolerance, not whether it feels small.
  • Measuring diameter with a ruler. On deformed bar, a direct measurement has to account for the ribs. Weighing is more reliable: take one full bar, weigh it, and compare against the table.
  • Using non-standard lengths without adjusting. Offcuts or 11-metre bars will never match the per-bar column. Work from the weight per metre instead.
  • Accepting undersized bar because the price looks good. A bar with an actual diameter of 15.2 mm sold as D16 carries only about 90 percent of the correct weight. What is missing is not only mass but load-bearing capacity.

The check is straightforward: request the mill certificate for the batch, match the batch number on the tag against the document, then weigh one random bar as a cross-check. Our certification page explains what those documents contain.

Frequently Asked Questions

Do plain and deformed bars weigh differently?

No. At the same nominal diameter they weigh exactly the same, because the SNI formula depends only on diameter. The difference lies in bond strength and grade.

How much does one D13 bar weigh?

A 12-metre D13 bar weighs 12.50 kg, from 1.042 kg per metre multiplied by twelve metres.

How many D10 bars are in one tonne?

About 135 bars, since a single D10 bar weighs 7.40 kg. For large orders, recalculate from the weight per bar to avoid a shortfall of several kilograms.

Will a real delivery match this table exactly?

The table gives theoretical weights from the SNI formula. Actual deliveries may deviate within the tolerance the standard permits. Anything beyond that tolerance should be raised with your supplier.

Which sizes does Inter World Steel produce?

We produce plain and deformed reinforcing bar from 8 to 40 mm across two rolling mills. Grade-by-grade details are listed on our product specification page.

Check before you sign

A weight table is the cheapest quality-control tool a rebar buyer has. A scale and a calculator are enough to establish whether a delivery matches the order, with no laboratory involved. We suggest contractors keep this table at the goods-receiving point.

PT Inter World Steel Mills Indonesia is a steel mill in Tangerang with more than 50 years of experience, certified to SNI 2052:2024, supplying SPPT-SNI and a mill certificate for every batch. For project requirements, see our Premium Rebar line, review the partnership terms on our rebar distributor page, or contact our team to discuss the sizes and volumes you need.