About

Procurement managers and warehouse teams frequently face the challenge of ordering or inventorying hardware by weight rather than count. This utility provides a bi-directional conversion between the number of washers (pieces) and their total mass (kg). Accurate weight estimation is essential for shipping logistics, where freight limits apply, and for purchasing, where hardware is often sold by the kilogram.

This tool features an extensive database of standard steel washers, including DIN 125 (Flat), DIN 127 (Spring), and DIN 9021 (Wide/Fender). By selecting the specific standard and thread size (M3 through M64), the tool retrieves the standard unit weight defined in engineering tables to calculate the total bulk mass. A custom weight option is available for non-standard or specialty alloy washers.

Formulas

The calculation is a simple linear relationship based on the unit weight (w) derived from the lookup table.

{

Total Weight = Quantity × w_(g)1000 (for kg)Quantity = Total Weight_(kg) × 1000w_(g)

Note: Unit weights are based on carbon steel (ρ ≈ 7.85 g/cm³).

Reference Data

Standard	Size (M)	Unit Weight (g)	1000 pcs Weight (kg)
DIN 125 (Flat A)	M6	1.14	1.14
DIN 125 (Flat A)	M10	4.08	4.08
DIN 125 (Flat A)	M20	17.20	17.20
DIN 127 (Spring B)	M8	1.60	1.60
DIN 9021 (Wide)	M12	22.30	22.30
DIN 440 (Wood)	M10	13.40	13.40
DIN 125 (Flat A)	M30	53.30	53.30

Frequently Asked Questions

Yes, generally. Carbon steel and stainless steel (A2/A4) have very similar densities (~7.85 g/cm³ vs ~7.9-8.0 g/cm³). The variation is usually within 1-2%, which is acceptable for bulk estimation.

Yes. This is a common technique called "weigh-counting". By weighing a bulk container of washers and subtracting the container weight, you can use the "Weight to Count" mode to estimate the number of pieces inside instantly.

We cover the most common DIN standards. For specialized thick washers or structural washers (like DIN 6916), use the "Custom" option and weigh a single sample piece to get the unit weight.