Washer Standards & Dimension Reference

They are closely equivalent. DIN 125 A and ISO 7089 are both plain flat washers, product grade A, with very similar inside diameter, outside diameter and thickness across the common metric range — so for most assemblies they are interchangeable. ISO 7089 is the current international reference and DIN 125 the long-established German standard. Tell us which one your drawing calls out and we build to it.

Both are flat washers, but DIN 9021 (large-OD / fender washer, ISO 7093 equivalent) has a much larger outside diameter — roughly three times the nominal thread size — to spread load over soft, slotted or oversized holes. DIN 125 is the regular-OD general-purpose flat washer. Use DIN 9021 for sheet metal, soft materials and slotted connections; use DIN 125 for standard bolted joints.

Yes. Beyond the DIN, ASME, ISO and GB standards listed here, we stamp non-standard washers to your drawing or sample — special outside diameter, inside diameter, thickness, chamfers, hole shapes and material or finish. Send a print or a sample with the tolerances that matter and we quote against it, with first-article inspection on request.

DIN standards (Germany) are metric; they define dimensions in millimetres with tolerances to product grade A or C. ASME B18.21.1 is the US inch-series standard — it covers Type A plain washers in two OD patterns (SAE narrow, USS wide) dimensioned in inches. The two systems do not share a common dimensional baseline, so an M6 DIN 125 is not interchangeable with a 1/4" SAE washer. Our automated coil-fed stamping line handles both metric DIN and inch ASME series; tell us which standard and size your drawing calls out.

Yes. We produce metric washers from M2 to M64 to DIN, ISO and GB references, and inch-series washers to ASME B18.21.1 / USS / SAE. If your drawing mixes systems or you need a conversion, send the controlling dimensions and we build to the print — not to a guess. Material grades (304, 316, 316L) are the same for both series.

Our flat washer production references ISO 7089 (plain, product grade A), ISO 7090 (plain, chamfered) and ISO 7093 (large OD / fender). For Chinese GB: GB/T 97.1 (grade A), GB/T 97.2 (chamfered) and GB/T 95 (grade C) flat washers. We also produce to JIS B 1256 (Japan), BS, NF, KS and UNI as required. Cross-standard equivalents — for example, DIN 125 ≈ ISO 7089 ≈ GB/T 97 ≈ JIS B 1256 for regular-OD plain washers — are available on request.

Yes, and we do it routinely — the table above covers the main pairings. Keep in mind these are nearest equivalents, not identical specifications: tolerances, surface condition and available size ranges can differ between standards. When your drawing calls out a specific standard, we build to that standard rather than substituting an equivalent. If you need a formal comparison for a procurement decision, tell us the standards and sizes and we will advise directly.

We manufacture to ISO 9001:2015 (cert. 74326Q00174R001) with standardized, documented processes and first-article inspection on custom parts. We verify the grade with our own handheld XRF spectrometer (PMI) and can include the reading with your order. Conformance documentation is stated on the relevant shipping document; if your project requires a specific certificate format, tell us upfront and we confirm what we can issue before you order. We cannot issue EN 10204 3.1 mill certificates.