Stainless washer size finder
Pick a standard and a size — metric DIN / ISO / GB/T or the US SAE and USS inch series. You get the exact inner diameter, outer diameter and thickness, plus an approximate weight per 1000 pieces and the matching equivalent standard numbers. All figures are the nominal dimensions we stamp to at our Jiaxing factory.
1, Choose the washer type / standard
Nominal dimensions in the unit shown — millimetres for DIN / ISO / GB/T, inches for the SAE and USS inch series (ASME B18.21.1 basic sizes). Tolerances are per the standard. Weight is a calculated estimate for a plain flat ring and will vary slightly with tolerance and chamfer. Other sizes and metric-to-inch cross-overs available on request — ask for a quote.
DIN 125 — full size table
Every size in the selected standard. The row you picked above is highlighted.
| Thread | Inner Ø d1 (mm) | Outer Ø d2 (mm) | Thickness s (mm) |
|---|
Full spec pages & related tools
DIN 125 flat washers
Standard-OD flat washer, M2–M64 in 304 / 316 / 316L, with tolerances and PMI grade check. DIN 125 page
DIN 9021 fender washers
Large-OD washers for soft, slotted or oversized holes. DIN 9021 page
DIN 433 small-OD washers
Narrow outer diameter for a tight bearing surface. DIN 433 page
GB/T Chinese standard washers
GB/T 97.1 / 95 / 97.2 and how they map to DIN and ISO. GB/T page
Identify a washer you have measured
Bore-to-bolt chart and how to tell DIN 125, 433, 9021 and SAE/USS apart by OD and thickness. Identification guide
DIN ↔ ISO ↔ ASME cross-reference
One table matching every washer standard to its equivalents. Cross-reference
Weight calculator
Enter your own dimensions and quantity for a shipping-weight estimate. Weight calculator
Common questions
Which standard is a “standard” flat washer?
For a normal-series metric flat washer, DIN 125 Form A is the common choice — outer diameter about 2 to 2.5× the bolt. ISO 7089 and China’s GB/T 97.1 share the same nominal dimensions, so a DIN 125 A washer fits a hole specified to any of the three.
What is the difference between DIN 125, DIN 9021 and DIN 433?
They differ mainly in outer diameter for the same bolt. DIN 433 is the small (narrow) OD, DIN 125 the standard OD, and DIN 9021 the large OD (fender / penny washer) used to spread load over soft or oversized holes. Inner diameter is close across all three for a given size.
How is the weight per 1000 washers calculated?
The finder estimates the flat-ring volume — (π / 4) × (outer² − inner²) × thickness — and multiplies by the stainless density (7.93 g/cm³ for 304, 7.98 for 316). It is a nominal estimate; real shipping weight varies slightly with tolerance and any chamfer.
Do the dimensions change between 304 and 316 stainless?
No. The geometry is set by the dimensional standard, not the material. 304, 316 and 316L washers to the same standard and size share the same inner Ø, outer Ø and thickness — only the alloy and the weight change slightly.
Found your size? Get a factory price.
Send the standard, size, material and quantity — we quote FOB or CIF from China, with XRF grade check (PMI) on request.