O-Ring Calculator and Seal Design Tools
Design an O-ring groove, calculate squeeze, stretch and gland fill, match standard sizes, assess extrusion risk and document the result in one engineering workflow.
- No account required
- Metric and inch units
- Nominal, minimum and maximum results
Online O-ring design built around engineering decisions
O Ring Design is an online O-ring engineering platform, not a product catalogue. It connects deterministic seal calculations with size standards, material selection and practical design guidance so an engineer can move from dimensions to a reviewable result.
Each calculator evaluates nominal and tolerance-limit conditions. Use the result to identify undersqueeze, overfill, stretch, extrusion and other design risks before confirming the final geometry against the applicable standard, compound data and operating conditions.
O-Ring design calculators and verification tools
Choose the seal geometry or engineering check that matches the hardware.
Tools, standards, materials and engineering knowledge
Four connected topic areas support the same O-ring design decision from different angles.
Engineering calculators
Calculate groove geometry and verify squeeze, stretch, fill and pressure-related risks.
Size standards and brand resources
Compare inch and metric size systems, identify the nearest standard designation, then verify brand-specific part data at its official source.
Material selection
Compare elastomer families by medium, temperature, hardness and service conditions.
Engineering guides
Understand the calculation methods, acceptable ranges and common failure mechanisms.
From O-ring size selection to design verification
A consistent path keeps the geometry, material and operating assumptions connected.
1. Define the duty
Choose static, dynamic, face, boss or retained-groove service and enter pressure, temperature and medium.
2. Select the size
Use measured dimensions or compare standard candidates from AS568, ISO 3601 and GB/T 3452.1.
3. Verify the gland
Check squeeze, stretch, gland fill, clearances and extrusion risk across the tolerance stack.
4. Record the result
Export a focused report for the selected seal form, including inputs, limits, binary qualification verdicts and a server integrity check.
Move from a checked design to supplier discovery
Carry material, hardness, size, application, certification and country requirements into the supplier network. Commercial visibility is disclosed and never changes engineering limits, matching distance or qualification verdicts.
- Filter manufacturers by verified capability
- Open a structured request for quote from a supplier profile
- Keep sourcing status separate from engineering judgement
From the Knowledge Center
View all guidesO-Ring Tolerance Stack-Up for Squeeze and Gland Fill
How O-ring and groove tolerances combine into minimum squeeze, maximum squeeze, stretch and gland fill, with a worked worst-case method.
GuideFKM vs NBR O-rings: how to choose
Compare FKM (Viton) and NBR (nitrile) O-rings by temperature range, chemical and fuel resistance, cost and typical applications, with a quick selection guide.
GuideHow to Measure an O-Ring
Measure O-ring inner diameter, outer diameter and cross-section correctly, convert between them, and match your measurements to AS568 or ISO 3601 standard sizes.
Built for demanding industries
Why O Ring Design
Complete calculation coverage
Static, dynamic, face, boss, crush, dovetail and non-circular face seals in one place.
Rich material database
Compare elastomers by media, temperature range, hardness and duty suitability.
Transparent engineering rules
Squeeze, gland fill, stretch and extrusion checks with the reasoning shown.
Design reports
Turn a selected seal calculation into a focused, shareable design summary.
Multiple seal structures
One workflow spanning the seal types real hardware actually uses.
Built for real engineering
Focused on practical design and verification, not marketing.
Frequently asked questions
What is O-ring squeeze?
Squeeze is the diametral compression applied to an O-ring cross-section when it is installed in a groove, usually expressed as a percentage of the cord diameter. Correct squeeze is what creates and maintains the seal.
What is gland fill?
Gland fill is the percentage of the groove volume occupied by the O-ring. It must leave room for thermal expansion and swell; too high a fill can over-stress the seal and the groove.
Static seal vs dynamic seal — what's the difference?
A static seal has no relative motion across the sealing interface, while a dynamic seal must accommodate movement. Dynamic applications drive tighter limits on squeeze, surface finish and friction.
Start with your engineering question
Find a measurement method, understand a calculation result, or browse the complete engineering library.
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