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Open calculator ↗FLEXIBLE CIRCUITS / PRACTICAL ENGINEERING
Flex PCB.
Designed around
your next idea.
Understand the materials. Plan the bend. Build a better quote package. Your starting point for flexible printed circuits, from first layout to fabrication.
SINGLE-SIDED / DOUBLE-SIDED / MULTILAYER / RIGID-FLEX
THE BASICS, WITHOUT THE GUESSWORK
What is a flex PCB?
A flex PCB is a printed circuit built on a flexible dielectric film, with patterned copper that carries signals and power. Polyimide is a common substrate; other films suit particular processes and environments.
Flexibility lets a circuit fit a three-dimensional enclosure. Repeated motion is a separate design requirement: a circuit that bends during installation is not automatically suitable for continuous flexing.
Start with the design guide →ANATOMY / EXAMPLE DOUBLE-SIDED FLEX
Coverlay filmProtection
Coverlay adhesiveBonding
Copper circuit L1Conductor
Polyimide coreDielectric
Copper circuit L2Conductor
Coverlay adhesiveBonding
Coverlay filmProtection
Simplified adhesiveless-base construction. Not to scale. Openings, plating and local stiffeners are omitted.
ENGINEERING WORKBENCH
Turn questions into
design decisions.
Explore a construction before you send files. Every result shows its assumptions and the next question to take to your fabricator.
Stackup builder
See copper, dielectric and coverlay layers. Separate flex thickness from local reinforcement.
Build a stackup ↗Material selector
Build a material shortlist around motion, temperature, budget and signal requirements.
Compare materials ↗Cost estimator
Explore an illustrative budget range. Carry your build parameters into the quote brief.
Estimate a budget ↗CHOOSE THE CONSTRUCTION
Start with the simplest
circuit that works.
Layer count changes routing freedom, total thickness and bending behaviour. A local stiffener and a rigid-flex section serve different purposes.
| Construction | What it gives you | What to check | Explore |
|---|---|---|---|
| Single-sided | One copper layer; a simple interconnect | Routing capacity and bend-life requirements | Single-sided flex → |
| Double-sided | Two copper layers with interlayer connections | Via placement, finished thickness and bend zone | Double-sided flex → |
| Multilayer | Additional routing and reference layers | Bonding construction, stiffness and tolerances | Multilayer flex → |
| Rigid-flex | Integrated rigid component areas and flexible links | Transitions, assembly support and cost | Rigid-flex design → |
MATERIALS
The film is only one part of the choice.
Compare the substrate, copper foil, coverlay adhesive and stiffener together. For repeated motion, specify a copper system and test plan suited to the actual duty cycle.
PI, PET, LCP and copper →DESIGN
Define the bend zone early.
Keep pads, vias and components outside the moving bend region. Coordinate trace routing, copper distribution and strain relief with the fabricator before locking the outline.
Design rules and stackups →COST
Price the whole construction.
Panel utilisation, layer count, tooling, stiffeners and inspection affect cost. Compare quotations with the same material, finished thickness and test requirements.
Understand the cost drivers →APPLICATION REQUIREMENTS
Small spaces. Different demands.
These are design use cases, not customer case studies. Identify what your product asks the circuit to survive.
Wearables
Limited space, skin-adjacent heat and repeated handling.
Design considerations →Medical devices
Traceability, environmental exposure and documented verification.
Build requirements →Automotive
Vibration, thermal cycling and connector retention.
Reliability questions →Cameras & displays
Fine-pitch interconnects, shielding and installation geometry.
Interconnect planning →FROM FILES TO FINISHED CIRCUIT
A clearer path to fabrication.
Review the design
Check files, stackup, bend geometry and acceptance criteria.
Form the circuits
Pattern copper and create interlayer connections where required.
Laminate & protect
Apply the specified bonding films, coverlays and stiffeners.
Finish & profile
Complete surface finishing and the circuit outline.
Inspect & verify
Use the agreed electrical and dimensional inspection plan.
Compare the information requested for flexible PCB manufacturing and custom flexible circuit boards when preparing your fabrication brief.
SPECIFICATIONS THAT CAN BE VERIFIED
Define acceptance
before production.
IPC-2223 addresses flexible and rigid-flex board design. IPC-6013 addresses qualification and performance. Agree the applicable revision, class and test requirements in procurement documentation.
Include in your quote package
Layer construction · finished thickness · material grade · copper type · bend radius and cycle target · impedance requirements · inspection criteria · quantity and required date.
Manufacturing limits, certifications and delivery commitments will be shown only after supporting information is confirmed.
PRACTICAL ANSWERS
Before you commit the design.
What is the difference between flex PCB and rigid-flex PCB?
A flex PCB uses a flexible base through its circuit structure. Rigid-flex integrates rigid board regions with flexible interconnect regions. A stiffener supports a local area of a flex circuit; it does not add the electrically interconnected layers of a rigid-flex section.
Can every flex PCB bend repeatedly?
No. A bend-to-install design may not survive repeated motion. Dynamic flex requires a review of copper type, geometry, finished thickness, bend direction and cycle-life testing.
Is coverlay the same as solder mask?
No. Conventional coverlay is a dielectric film bonded with adhesive, with openings for connection pads. Flexible solder masks use different materials and processing. Specify the actual protective system and opening tolerances.
What files are needed for a flex PCB quote?
Start with fabrication data, a board outline, drill data, stackup and material notes. Add quantities, bend requirements and the required date. For assembly, include the BOM, placement data and assembly drawings.
Why does a smaller flex PCB not always cost less?
Board area is only one input. Irregular shapes can reduce panel utilisation; additional layers, tooling, stiffeners and test requirements can increase cost. Compare the full build specification.
Can flex PCBs have vias?
Yes. Double-sided and multilayer constructions can use plated interconnections. Keep vias outside moving bend regions and confirm the pad, drill and plating requirements with the fabricator.
What are the downsides of flexible PCBs?
Flexible circuits need careful handling, defined bend regions and support during assembly. Tight material and registration requirements can raise fabrication cost. They cannot stretch like an elastomer, and a static design does not automatically meet a repeated-motion requirement.
How much does a flex PCB cost?
Price depends on the complete construction, panel utilisation, order quantity, tooling and inspection scope. Use the estimator to explore illustrative budgeting assumptions, then request a written quote based on your fabrication files.
YOUR NEXT STEP
Bring the requirements.
Start the conversation.
Tell us what the circuit needs to do, how it will bend and when you need it. A complete build brief makes a quote easier to evaluate.
Preparing files?
Include Gerber and drill data, a fabrication drawing and stackup notes. Put related files in one ZIP. Add a BOM and placement file when assembly is required.