Custom Insole Manufacturing FAQ

S-King manufactures custom insoles for sports, comfort, work, casual, outdoor, orthopedic, medical and children’s footwear applications.

Our manufacturing capabilities include EVA, PU, TPE gel, carbon fiber and multi-material insole constructions. Product structure, cushioning zones, support areas, thickness, hardness, colors and surface materials can be customized according to the project requirements. See the full custom insole products we manufacture range.

Yes. S-King provides both OEM and ODM insole manufacturing.

OEM is suitable for customers who already have drawings, samples, technical specifications or an existing product design. ODM is suitable for customers who have a product concept or performance requirement and need support with structure development, material selection, prototyping, mold development and manufacturing.

Yes. You can provide a physical sample, technical drawing, product specification or existing design.

Our team can evaluate the structure, materials, dimensions and manufacturing process before developing samples and preparing the product for mass production.

Yes. Our ODM service supports customers from initial product concept through design, material selection, mold development, sampling and mass production.

You can start with a drawing, reference sample, target application or simply a list of product requirements.

A typical project follows six stages:

Before production begins, the product structure, materials, dimensions, performance requirements and customization details are confirmed with the customer. You can read more about our insole production line.

S-King’s standard MOQ starts from 100 pairs, but the actual MOQ depends on the product, materials, manufacturing process and level of customization.

Projects using an existing mold or standard construction may have different requirements from projects involving new tooling, special materials or fully customized structures.

Yes. Sampling is an important part of the custom development process.

Samples allow you to evaluate product dimensions, fit, structure, materials, cushioning, surface finish and other specifications before approving mass production.

Typical prototype development takes approximately 7–15 business days, depending on the complexity of the product, materials and whether new molds or tooling are required. For simple projects using existing molds, the sampling process may be faster.

Yes, depending on the project.

S-King supports customization of materials, colors, fabrics, structures and branding. Sample specifications should be confirmed before production so the sample can represent the intended final product as closely as possible.

Providing more project information helps us prepare a more accurate quotation. Useful information includes:

• Insole type
• Target application
• Product dimensions
• Material preference
• Structure or performance requirements
• Logo requirements
• Packaging requirements
• Estimated order quantity
• Reference samples, drawings or photos

S-King can also provide recommendations if some specifications have not yet been finalized.

S-King works with a wide range of insole materials including:

• EVA
• PU
• PORON®
• TPU
• TPE
• Gel
• Carbon Fiber

Different materials can be selected according to cushioning, support, flexibility, weight, durability and footwear application requirements.

The materials serve different product requirements.

• EVA is lightweight and can be produced in different densities and hardness levels.
• PU foam generally provides resilient cushioning and is commonly used for comfort and long-wear applications.
• Memory foam is often selected for soft, pressure-responsive comfort layers.

The best choice depends on the footwear type, target feel, thickness, durability requirements and product positioning. For a side-by-side view, see our PU vs EVA vs memory foam insole comparison.

Material selection should begin with the intended application rather than the material name alone. Our team considers factors such as:

• Cushioning
• Support
• Flexibility
• Thickness
• Weight
• Durability
• Target footwear
• Production process
• Target price range

S-King’s design and R&D team supports material selection during product development.

Yes. Multi-material construction can combine different layers or functional areas to achieve different cushioning, support, stability or durability characteristics.

For example, foam materials can be combined with support structures, gel zones, reinforcement materials or different surface fabrics depending on the product design.

Yes. S-King supports customization of material hardness, thickness, color and other product specifications depending on the manufacturing process and material used.

Our PU, EVA and TPE gel production capabilities support different material and structural requirements.

No. S-King maintains more than 1,000 existing insole molds covering different shapes, sizes, structures and product types.

If an existing mold meets the project requirements, it may help reduce tooling cost and shorten development time. A new mold is normally considered when the required geometry or structure cannot be achieved with existing tooling.

Yes. S-King supports custom mold development for different insole shapes, sizes and structures as part of OEM and ODM development projects.

Yes. Product geometry such as arch profile, overall shape, thickness and support structure can be developed according to the customer’s product specifications and intended footwear application.

These requirements should ideally be confirmed before mold development begins.

Yes. Custom designs may include different cushioning areas, support structures, gel zones, reinforcement elements, thickness profiles and material combinations.

The final construction depends on the product application, target performance and manufacturing method.

The timeline depends on mold complexity, size range, material, structure and the number of revisions required.

The process normally includes design confirmation, tooling, trial samples, measurement, evaluation and adjustment before the mold is approved for production.

For this reason, the final tooling schedule should be confirmed after the product specifications are defined.

Yes. S-King supports custom logo and branding options for OEM and private-label projects.

The available logo method depends on the product surface material, structure and manufacturing process.

Private-label customization can include:

• Product logo
• Color
• Surface fabric
• Materials
• Sizes
• Packaging
• Labels
• Barcodes

These options allow brands and distributors to develop products that match their own brand positioning.

Yes. S-King supports customized fabrics, colors, materials and branding depending on the product design and production process.

Color and logo requirements should be confirmed during sampling to help maintain consistency during mass production.

Yes. Available packaging options include retail boxes, gift boxes, poly bags, hang tags, pouches and other private-label packaging formats depending on the project requirements.

S-King can support private-label packaging requirements, including custom boxes, bags, labels and barcodes.

For projects requiring a completely new packaging structure or artwork, the exact design requirements should be discussed with our team before quotation.

Production time depends on the product type, order quantity, materials, tooling requirements and packaging.

Once the sample and specifications are approved, our team can provide a production schedule based on the actual project.

The complete timeline normally includes:

Prototype development is typically around 7–15 business days, while the production schedule depends on project complexity and order volume.

Yes. S-King operates specialized production lines for several major insole materials. Current listed monthly capacities include:

• EVA: 168,000 pairs
• TPE Gel: 50,000 pairs
• PU: 39,000 pairs
• Carbon Fiber: 11,000 pairs

The actual available capacity should be confirmed according to the product and production schedule.

Yes, subject to the agreed project and tooling arrangement.

Approved product specifications, materials, tooling and reference samples help provide a consistent basis for future repeat production.

For custom tooling projects, mold ownership and use terms should be agreed before tooling begins.

S-King uses approved specifications and quality-control procedures to compare production against the confirmed product requirements.

Quality checks cover incoming materials, dimensions, appearance, assembly and packaging.

For custom development, keeping an approved reference or golden sample also provides a clear physical standard for production comparison.

Quality control begins with incoming material inspection and continues throughout the manufacturing process.

S-King’s QA/QC team monitors materials, production processes, dimensions, appearance, assembly and packaging before shipment.

Inspection requirements depend on the product, but the manufacturing process includes:

• Raw material inspection
• In-process inspection
• Dimension checks
• Appearance inspection
• Assembly inspection
• Packaging inspection
• Final product inspection

The objective is to confirm that the finished product matches the approved specifications before shipment.

S-King currently lists the following certifications and compliance credentials:

• CE conformity
• ISO 9001
• ISO 13485
• ISO 14001
• ISO 45001
• amfori BSCI
• SGS on-site factory verification

See our certifications and compliance documents for details. Relevant documents should always be checked against the specific product, material and destination-market requirements.

Testing requirements vary by product, material and destination market.

S-King can work with customers to identify relevant material documentation, test requirements, product specifications and compliance needs before mass production.

Any specific third-party testing requirement should be discussed during project development.

Material control should start before production rather than only checking finished goods.

S-King’s quality process includes incoming-material inspection together with in-process and final inspections. Approved specifications are then used to help maintain consistency during production.

S-King develops custom insoles for a range of footwear applications including:

• Sports and running shoes
• Casual footwear
• Work and safety footwear
• Hiking and outdoor footwear
• Orthopedic and healthcare applications
• Kids’ footwear
• Fashion and dress footwear

Each application can require different combinations of cushioning, support, thickness, materials and durability.

Yes. S-King develops sports insoles for running, training, hiking and other active footwear.

Depending on the project, sports insoles can be developed around requirements such as lightweight construction, cushioning, stability and support. See our work on sports and running footwear.

Yes. S-King develops insoles for work and safety footwear, where durability, cushioning and long-wear comfort are often important design considerations.

PU and gel constructions are among the options available for these applications.

Yes. Comfort and casual insoles can be developed using lightweight and cushioned constructions for everyday footwear and prolonged wear.

Yes. The product structure can be adjusted according to the footwear application, including:

• Shape
• Thickness
• Cushioning
• Support areas
• Material
• Hardness
• Flexibility
• Surface fabric

Rather than using one insole construction for every shoe, we recommend developing the product around the intended footwear and target user requirements.

Send us your product idea, drawing, reference sample or technical requirements.

Our team can then evaluate the project and recommend suitable materials, structures and manufacturing options before sampling begins.

For an OEM project, it is helpful to provide:

• Physical sample or drawing
• Dimensions
• Materials
• Product structure
• Performance requirements
• Color
• Logo
• Packaging
• Quantity
• Target market

If some details are still undecided, S-King can assist with material and manufacturing recommendations.

Yes. S-King works with footwear brands, wholesalers, distributors, retailers and product developers on custom insole manufacturing projects. Learn more about S-King.

Yes. S-King supplies international customers and currently states that its OEM and ODM products are exported to customers across 50+ countries.

Project requirements such as packaging, documentation and compliance should be confirmed according to the destination market.

Yes. S-King supports customers from initial development and sampling through mass production, quality control, private-label packaging and repeat production.

For long-term programs, maintaining approved specifications, reference samples and clearly defined material and tooling requirements helps improve consistency across repeat orders.