A free toolkit for engineers building rigid-flex boards: visualise the stackup, calculate the safe flex bend radius, and estimate cost & complexity — then take it to manufacturing.
Everything below runs right in your browser — no sign-up, no data leaves the page. Built by PCBSync for the people who actually route these boards.
Pick your flex and rigid layer counts and instantly see the physical cross-section, layer table and finished thickness.
Open builder →Get the IPC-2223 minimum bend radius for your flex section — static or dynamic — so cracked copper never ships.
Open calculator →Model how layers, flex content, area, finish and volume drive your rigid-flex price before you commit to a design.
Open estimator →In a rigid flexible PCB the flex core runs continuously through the board, while extra rigid layers build up only in the rigid zones. Configure it and watch the cross-section update.
Bend a flex circuit too tightly and the copper cracks. These IPC-2223 ratios give the minimum inside bend radius for your construction and use case.
See how each design choice pushes your rigid-flex price. Numbers are indicative ballpark figures to guide trade-offs — get a firm quote from PCBSync before you build.
↳ Ready for real pricing on your rigid flexible PCB? PCBSync turns these specs into a manufacturable quote.
Get a firm quote ↗Hard-won DFM rules for laying out a reliable rigid flexible PCB. Hover any card.
Build rigid layers symmetrically around the flex core. Unbalanced copper and dielectric distribution causes the panel to warp after lamination.
Route the flex so the bend axis is perpendicular to the traces, and never place a bend across the rigid-to-flex transition. Bend only in the pure flex zone.
Keep copper features and vias ~0.5 mm clear of the rigid-flex transition. This stress-relief zone is where most flex failures start.
Use curved or 45° trace routing on the flex — sharp 90° corners concentrate stress. Stagger traces on opposite layers (no stacked copper) to stay flexible.
Replace solid copper pours in the flex region with a cross-hatch polygon. Solid copper stiffens the flex and is prone to cracking when bent.
Never place plated through-holes or vias in a flexing area. Add teardrops to pads and use larger annular rings in the flex to survive flexing.
Add FR4 or polyimide stiffeners under connectors and component areas on the flex so solder joints aren't loaded when the board flexes.
For tight bends and many flex cycles, choose adhesiveless polyimide. It's thinner, more flexible and far more reliable than adhesive-based flex.
Rigid-flex tolerances vary by shop. Share your stackup and bend requirements with the fabricator before layout to lock in achievable rules.
Typical rigid flexible PCB builds, where they're used, and how they trend on cost & complexity.
| Configuration | Rigid / Flex | Typical use | Relative cost |
|---|---|---|---|
| 2-Layer Flex | 0 rigid + 2 flex | Simple jumpers, dynamic cable replacements, LED strips | |
| 4-Layer (2R+2F) | 2 rigid + 2 flex | Wearables, small sensors, camera modules — entry rigid-flex | |
| 6-Layer (4R+2F) | 4 rigid + 2 flex | Mainstream consumer & industrial controllers with a flex tail | |
| 8-Layer (6R+2F) | 6 rigid + 2 flex | Medical, RF and dense designs needing power/ground planes | |
| 10-Layer (6R+4F) | 6 rigid + 4 flex | Aerospace, defense, high-reliability multi-fold assemblies |
The polyimide flex layers are imaged, etched and covered with coverlay to form the continuous flexible sub-core.
FR4 cores and prepreg are laminated onto the flex sub-core only in the rigid zones, then drilled and plated.
Controlled-depth routing or laser cuts free the flex windows, leaving the rigid sections intact. Then test, finish and profile.
Rigid-flex shines wherever you need to fit a reliable circuit into a tight, moving or 3D space.
Hearing aids, patches, implants and monitors that must be tiny, light and bend to the body.
Vibration-proof, weight-saving interconnects for avionics, satellites and guidance systems.
Cameras, ADAS sensors, instrument clusters and battery packs in harsh, high-vibration environments.
Foldable phones, laptops, cameras and earbuds where every cubic millimetre counts.
Articulating joints, end-effectors and machinery that flex through millions of cycles.
Compact nodes and edge devices that wrap around enclosures and antennas.
Rugged radios, optics and field gear demanding maximum reliability per gram.
Driver boards that fold behind panels in TVs, instrument displays and AR/VR optics.
You've designed it here — now build it. Send your rigid-flex specs to PCBSync for fabrication, assembly and full DFM support.
Manufacture with PCBSync ↗