If you've been told you need orthotics, you've probably encountered two main categories: prefabricated (off-the-shelf) and semi-custom (heat-mouldable or clinician-modified). Both support the arch and correct foot biomechanics — but they differ in how closely they match your individual foot, how much they cost, and how effective they are for different conditions. Here's what you need to know.
What are prefabricated orthotics?
Prefabricated orthotics are pre-made insoles manufactured to a standardised foot shape. They come in set sizes and densities, and are ready to wear straight from the pack. The best prefabricated orthotics — like the Trekker Full Length orthotics — are engineered with specific biomechanical features (heel cups, medial skives, arch contours) that address the most common foot pathologies without needing custom modification.
Prefabricated doesn't mean inferior. A well-designed prefabricated orthotic from a reputable brand can outperform a poorly made custom device. The key is the quality of the biomechanical design, not whether it was made for your foot specifically.
What are semi-custom orthotics?
Semi-custom orthotics start as a prefabricated base but can be modified to better match your foot. The most common approach is heat moulding — the orthotic is heated in a clinic oven and moulded directly to your foot by a podiatrist, creating a more personalised contour than a standard off-the-shelf device.
Formthotics insoles are the best-known semi-custom option in Australian podiatry. Made from thermoformable Formax™ foam, they can be heat-moulded in-clinic for a customised fit, or worn straight from the pack where they'll gradually conform to the foot shape over time.
When prefabricated orthotics are the right choice
- First-time orthotic users — trying a quality prefabricated orthotic before investing in custom devices is sensible. Many patients find prefabricated orthotics resolve their symptoms completely.
- Common conditions — plantar fasciitis, flat feet, arch pain, heel pain, and general overpronation respond well to prefabricated orthotics with appropriate arch support and heel cup depth.
- Budget considerations — prefabricated orthotics cost $45–$85 compared to $300–$600+ for fully custom devices.
- Multiple pairs of shoes — at a lower price point, you can afford orthotics in your work boots, runners, and casual shoes rather than transferring one expensive pair between shoes.
Our prefabricated range:
- Trekker Full Length Firm Density — for 50–80kg body weight
- Trekker Full Length Extra Firm Density — for 80kg+
- Trekker 3/4 Length Firm — for lower-volume shoes
When semi-custom orthotics are the better choice
- Unusual foot shapes — very high arches, very flat feet, or significant asymmetry between left and right foot
- Sport-specific performance — runners, cyclists, and footballers benefit from the closer fit of a heat-moulded insole inside performance footwear
- Conditions that need precise correction — tibialis posterior tendon dysfunction, severe overpronation, or complex biomechanical issues may need the closer contouring of a semi-custom device
- When prefabricated orthotics helped but weren't quite enough
Our semi-custom range:
- Formthotics Sport Run Dual — dual-density, heat-mouldable, ideal for running
- Formthotics Sport Run Single — thinner profile for tight shoes
- Formthotics Everyday Workfit — designed for work boots
- Formthotics Sport ShockStop — maximum cushioning for high-impact activity
What about fully custom orthotics?
Fully custom orthotics are prescribed by a podiatrist and manufactured from a 3D scan, foam impression, or plaster cast of your individual feet. They offer the highest level of customisation and are recommended when prefabricated and semi-custom options haven't provided adequate relief, or when complex structural deformities require precise correction. They typically cost $300–$600+ and take 1–2 weeks to manufacture.
For most people with common foot conditions, a quality prefabricated orthotic like a Trekker or a semi-custom Formthotics insole provides excellent results at a fraction of the cost. Your podiatrist can advise which level of customisation your foot type and condition require.
Quick comparison
- Immediate availability, lower cost, multiple pairs → prefabricated (Trekker)
- Closer fit, heat-mouldable, sport-specific → semi-custom (Formthotics)
- Complex deformity, failed conservative treatment → fully custom (see your podiatrist)