Flex PCB manufacturing — matched to the right manufacturer.
Upload your flex design and we find the manufacturer in our network with the right experience in polyimide flex circuits — free quote, free DFM check.
The technology
What is a flex PCB?
A flex PCB (flexible printed circuit) is built on a thin polyimide base instead of rigid glass-reinforced laminate, so the finished circuit can bend, fold or flex during use. Instead of a liquid solder mask, the copper is usually protected by a coverlay — a polyimide film laminated over the circuit with adhesive — with openings for pads. Flex circuits can be single-sided, double-sided or multilayer, and are often fitted with stiffeners behind connectors and components. A key distinction is static flex, which is bent once during installation, versus dynamic flex, which bends repeatedly in service and needs a more conservative design. The stack-up defines the layer order, adhesive or adhesiveless materials and where stiffeners sit.
Our network includes manufacturers experienced in flex circuits, from simple single-sided interconnects to multilayer flex.
Applications
When to choose a flex PCB
Choose a flex PCB when space, weight or movement rule out a rigid board with cables. Typical reasons and applications:
- Wearables and compact consumer devices, where the circuit must follow a curved or folded housing.
- Camera modules and displays, where a thin flex tail connects the module to the main board.
- Medical devices such as hearing aids, probes and patient monitoring equipment.
- Automotive sensors and lighting, where the circuit must fit irregular spaces and tolerate vibration.
- Replacing wire harnesses, cables and board-to-board connectors to reduce assembly steps and failure points.
- Hinges and moving parts, where a dynamic flex design survives repeated bending.
Design for manufacturing
Flex PCB design tips
- Follow the bend-radius guidance in IPC-2223 and agree the minimum bend radius with the manufacturer; dynamic flex needs a larger radius than static flex.
- Keep vias, pads and components out of bend areas. Plated holes and solder joints crack when the copper around them is flexed.
- Route traces perpendicular to the bend line, and stagger traces on double-sided flex so the copper on both sides does not sit on top of each other (I-beaming).
- Use curved traces instead of sharp corners and add teardrops at pads and vias to spread mechanical stress.
- Use hatched copper instead of solid planes in flex areas to keep the circuit flexible.
- Add stiffeners behind connectors and components, and specify rolled-annealed copper for dynamic flex because it withstands repeated bending better than electrodeposited copper.
Our free DFM check and the manufacturer's own engineering review help catch issues like these before production.
Checklist
What to send for a flex PCB quote
- Gerber files including coverlay and stiffener layers
- Board outline and drill files
- Fabrication drawing with the stack-up
- Bend areas, marked as static or dynamic
- Stiffener material and thickness
- Required thickness at the ZIF connector contact area
- Surface finish
- Quantity (prototype and expected production volume)
Upload your Gerber files. Get a free PCB quote.
We check your files for free and compare manufacturers in our network to find the best match. No obligation.
- Free quote
- Free DFM check
- 12 vetted manufacturers
What happens when you upload?
One of our engineers checks your Gerber files with our in-house DFM tool and emails you any findings within 72 hours. We then compare manufacturers in our network that fit your spec and send you the quote from the best match. Files are shared only with manufacturers we select, under NDA.
- Upload your Gerber files
- We check your files
- We compare manufacturers
- You get your quote
Free for you — you order directly from the manufacturer.
Common questions
FAQ about flex PCBs
What is a flex PCB?
A flex PCB is a printed circuit built on a thin, flexible polyimide film rather than rigid FR-4. The copper is protected by a polyimide coverlay instead of a solder mask. Flex circuits can be single-sided, double-sided or multilayer, and are used where a circuit must bend during installation or in service, or where it replaces cables and connectors.
What are the downsides of flexible PCBs?
Flex PCBs are more expensive per unit area than rigid boards, need more careful design around bend areas, and are harder to handle during assembly, often requiring carriers or stiffeners. Polyimide absorbs moisture, so boards may need baking before soldering. Repairs and rework are also more difficult than on rigid boards, and dynamic flex designs need extra validation.
How thick is a flex PCB?
A flex PCB is typically only a fraction of a millimetre thick, much thinner than a standard rigid board. The final thickness depends on the number of copper layers, the polyimide and adhesive thicknesses, the coverlay and any stiffeners. Where the flex plugs into a ZIF connector, the thickness of the contact area must match the connector specification.
Are flex PCBs more expensive than rigid PCBs?
Yes, per board a flex PCB usually costs more than a comparable rigid PCB, because polyimide materials, coverlay lamination and handling are more costly. At system level, however, flex can reduce total cost by replacing cables, connectors and assembly steps. Panel utilisation, layer count and stiffeners are the main cost drivers to review during design.
Specialist boards