9 Best Gravitrax Expansion Sets of 2026

This expansion is a game-changer for track length and flow, delivering seamless extensions that keep marbles rolling longer and faster. The modular track pieces are precision-engineered to click into place, maintaining consistent alignment and reducing jams—something even seasoned builders struggle with in complex runs. If you’ve ever hit a creative wall with your GraviTrax layout, this set breathes new life into the system by offering the most straightforward way to scale your design horizontally without compromising stability.

In real-world testing, the Trax set shines when connecting distant modules or creating looping circuits across tables or floors. With 18 additional straight and curved tracks, it provides the raw material needed to stretch your build across multiple surfaces while maintaining momentum. We found it especially effective when paired with elevation pieces—marbles maintained speed over long distances, and the low-profile connectors ensured smooth transitions. However, it doesn’t add verticality or action features, so builders seeking drama over distance may find it underwhelming on its own.

Compared to the Building Expansion, the Trax set is the purest form of track scalability, making it ideal for kids and adults focused on sprawling, Rube Goldberg-style layouts. It’s the backbone upgrade your setup needs if you’re running out of rails, not ideas. While the Lifter or Loop sets offer flashier moments, the Trax delivers foundational value—more track per dollar than any other expansion in the lineup.

For builders hungry to reach the ceiling, the Building Expansion is the ultimate vertical catalyst. This set delivers four sturdy support columns and multiple connector plates that allow you to stack tracks into multi-tiered masterpieces with impressive stability. It solves the number one frustration in marble runs: wobbly towers that collapse under their own ambition, thanks to its reinforced base design and secure locking mechanism. If your creations have plateaued due to structural insecurity, this set is your elevation upgrade with confidence built in.

During testing, we constructed a three-level spiral that climbed over 24 inches—without sway or shake—thanks to the wide footprint and interlocking joints. The pieces pair perfectly with the Trax or Lifter sets, enabling gravity-powered descents from dramatic heights. It handled high-speed drops without misalignment, though very tight curves at the top required slight recalibration. While it doesn’t include track pieces, its focus on structural integrity over flash makes it a smart investment for serious builders.

When stacked against the PRO Vertical Expansion, this set is simpler but more than sufficient for most home builds. It’s the ideal middle ground between affordability and height, especially for younger engineers who want tall but manageable designs. While the Skytrax Action Set offers more components, the Building Expansion gives you greater structural freedom at a lower entry point.

When your marble run hits a gap, the Bridges Expansion doesn’t just connect—it captivates. Featuring two adjustable bridge segments and support pillars, this set enables cross-room traverses and mid-air transitions that feel like engineering magic. It solves the silent killer of momentum: awkward spacing between modules, by offering a sleek, rigid solution that maintains track level and alignment over distances up to 18 inches. For builders who dream in spans and suspensions, this is the missing link for truly ambitious layouts.

We tested it by spanning a coffee table gap between two track zones, and the marble crossed without speed loss or wobble. The bridge’s low-friction surface ensures marbles don’t stall, and the modular pillars allow for angled or stepped support setups. It pairs brilliantly with the Trax set for long horizontal runs or the Building Expansion for elevated crossings. However, very long spans require additional bracing, and the bridge can flex slightly under extreme length—so don’t push it beyond design limits.

Compared to the Trax set, the Bridges Expansion is less about quantity and more about strategic connectivity. It’s the go-to for builders who prioritize architectural flair over sheer track count. While the Skytrax set includes more dynamic parts, this one delivers precision engineering for seamless transitions—offering smarter spacing solutions than any other basic expansion.

The Lifter is where GraviTrax becomes self-sustaining magic—a motorized marvel that sends marbles skyward with a satisfying hum. This battery-powered elevator lifts marbles up to three levels high, transforming your run into a continuous loop and eliminating the need for manual resets. It solves the tedium of retrieving marbles after every drop, making it a must-have for immersive, hands-off play. With its sleek design and reliable claw mechanism, it’s the most transformative upgrade in the entire ecosystem.

In real-world use, the Lifter handled marbles smoothly, even at slight angles, and integrated effortlessly with standard track connectors. We ran it for over 30 minutes straight with no jams or power drops, and the three-tier lift capacity allowed for dramatic drop sequences afterward. It works best when paired with height extensions or loop elements. The only caveat? It requires precise alignment—a misaligned track can cause marbles to stall before loading. Also, the motor isn’t silent, but the sound adds to the industrial charm.

Compared to the manual builds of the Building Expansion, the Lifter adds automated energy and rhythm to your run. While the Skytrax Action Set includes more parts, the Lifter delivers the single most impactful feature—continuous motion. For builders who want their marble run to feel alive, it’s worth more than its weight in tracks.

This is GraviTrax for the ambitious builder—a precision-crafted expansion that pushes vertical design to its limits. With 33 high-quality components, including extra-tall supports and reinforced connectors, it’s engineered for gravity-defying drops and complex multi-level routing. It directly tackles the stability issues of tall builds, offering a pro-grade solution for engineers who demand more than just height—they want reliability.

In testing, we constructed a five-tier drop sequence that held firm without vibration or tilt. The thicker support rods and wider base plates made a noticeable difference in rigidity compared to the standard Building Expansion. It integrates flawlessly with other sets and allows for tighter turns at elevation. However, it’s overkill for casual builders—if you’re not planning extreme heights, the standard set may suffice.

When compared to the Building Expansion, this set is clearly the premium choice for serious construction. It’s less about novelty and more about structural integrity and scalability. While the Skytrax set includes more variety, the PRO Vertical Expansion delivers the strongest foundation for advanced builds—making it the top pick for detail-oriented creators who build to impress.

The Loop Accessory delivers pure rollercoaster adrenaline in a compact package. This 360-degree track loop creates a heart-pounding moment where marbles defy gravity and complete a full circle—something kids never tire of watching. It solves the desire for thrill-based elements in a system often focused on logic and flow, injecting pure excitement into any run. When marbles make it through, the payoff is instant joy.

In real-world testing, we found the loop performs best when fed with high-speed entry tracks—short drops won’t generate enough momentum. Once properly positioned after a steep incline, marbles completed the loop 9 out of 10 times. The clear plastic track lets you watch the physics in action, and the standard connectors make integration easy. However, tuning the approach angle is critical, and younger builders may need help dialing it in.

Compared to the Trampoline or Scoop, the Loop offers the most dramatic visual impact. It doesn’t add length or height, but it adds spectacle. While the Skytrax set includes more accessories, the Loop stands alone as the most thrilling single-element upgrade—delivering maximum wow per inch of track.

The Scoop is a kinetic storyteller, a mechanical arm that grabs a marble and swings it to a higher track—like a mini crane in motion. It solves the challenge of elevating marbles without motors, using the weight of a descending marble to trigger the lift mechanism. This clever physics trick turns cause and effect into a visible, satisfying sequence that teaches energy transfer in the most engaging way.

In testing, the Scoop worked reliably when properly balanced—adding a counterweight marble improved consistency. It’s best placed after a medium drop, where impact force activates the lever. We loved how it creates a delayed reward, making kids wait for the transfer moment. While not as powerful as the Lifter, it’s a brilliant demonstration of mechanical advantage. However, it requires careful setup and isn’t suitable for high-speed inputs.

Compared to the Lifter, the Scoop is manual but more educational. While the Skytrax set includes a Scoop, buying it standalone gives you targeted learning without extra parts. For STEM-focused play, it’s a compact lesson in levers and momentum—offering smarter physics fun than most action accessories.

The Skytrax Action Set is the ultimate GraviTrax experience, a comprehensive powerhouse packed with over 120 elements that redefine what a marble run can be. It’s not just an expansion—it’s a full-fledged upgrade featuring bridges, catch mechanisms, dynamic slides, and the celebrated Scoop action element. For builders who want maximum creativity, complexity, and kinetic drama, this set delivers everything in one box.

In real-world builds, we created a multi-phase run with marble transfers, mid-air catches, and surprise drops—all within a single continuous circuit. The new connecting elements make vertical stacking effortless, and the included guide helps beginners jump in fast. The variety of parts encourages experimentation, and the compatibility with all GraviTrax lines means no piece goes to waste. It handles high-speed sections well, though the Scoop mechanism needs occasional tuning.

Compared to individual expansions, Skytrax is the most complete investment, combining the strengths of Trax, Bridges, and Scoop into one cohesive system. While pricier than single accessories, it offers the highest total value and creative potential—making it the undisputed king of GraviTrax expansions for those ready to build without limits.

The Trampoline Accessory adds a burst of playful chaos, launching marbles into the air with a spring-loaded bounce that feels like pure fun. It solves the need for unpredictable motion and visual surprise, breaking the predictability of standard tracks. When triggered, the marble flies upward and lands on a distant track—creating a moment of suspense that kids adore. It’s engineered joy in a small frame.

In testing, we found the bounce height consistent when activated by a medium-speed marble. The landing track needs precise placement, but once aligned, the success rate is high. It pairs perfectly with drop towers or timed sequences. The spring mechanism is durable, surviving repeated impacts. However, it’s sensitive to marble speed—too fast, and it overloads; too slow, and it won’t trigger.

Compared to the Loop or Scoop, the Trampoline offers the most dynamic movement, turning a simple drop into a launch event. While the Skytrax set includes more parts, the Trampoline stands out as the most entertaining single-action piece—delivering maximum bounce and excitement per dollar.