RIWI® Giant Building BlocksClick to enlarge

RIWI® Giant Building Blocks

The Original.

Build, climb, create — something new every time. No instructions in the box: they decide what it becomes.

  • Less screen time, more real play
  • Forts, castles & obstacle courses — rebuilt every day
  • Builds STEM skills, imagination & movement — ages 3+
  • Durable, safe, non-toxic — tested to ASTM F963
  • Every set: equal mix of blue · yellow · green · red
$279.95 $299.95Now $11.66 / block

Shipped from Houston, TX with USPS Ground · ✓ Free shipping included

Choose your set: 24 Blocks

The more they build with, the less each block costs.

Estimated delivery: 2–5 business days

  • 85,000+ parents trust RIWI® — in 30+ countries
  • 4.73★ · 712 verified reviews on riwi-buildit.us
  • 30-day returns — money back
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With a RIWI® set you get extra-large foam blocks that invite kids to build freely — a cozy cave, a rocket, a tall castle or a spaceship. Thanks to the giant size, kids build structures they can actually crawl into, so every game turns into a small adventure. The blocks stack and hold without any tools: put them together, build, play.

Size per block (H × W × D): 28 × 8 × 4 in (71 × 20 × 10 cm)
Weight per block: about 0.7 lb (0.32 kg)
Colors: blue, yellow, green, red — every set in an even mix
Age: 3+ — and sturdy enough for grown-ups (holds up to 242 lb / 110 kg)

Built for real family life: robust materials, kid-safe finishing and a soft, grippy feel that keeps play going for years.

Material & build

  • High-quality, tested polyurethane foam in mattress quality — soft, stable and shape-retaining
  • High-grip surface: blocks hold together on their own — no velcro, no magnets, no connectors
  • Built to last: high abrasion resistance for years of daily play

Safety

  • Tested to ASTM F963 (U.S. toy safety standard)
  • TÜV Austria tested to EN 71 — no harmful substances
  • No hard edges; holds up to 242 lb (110 kg)

Care

  • Machine-washable or hand-wash at 86 °F (30 °C)
  • Use a mild detergent — no fabric softener
  • Gently press out excess water and dry flat
  • Starter Set — 12 blocks: 3 blue · 3 yellow · 3 green · 3 red — about 8.6 lb (3.9 kg)
  • Family Set — 24 blocks: 6 of each color — about 17.4 lb (7.9 kg)
  • Giant Set — 36 blocks: 9 of each color — about 24.3 lb (11 kg)
  • Mega Set — 48 blocks: 12 of each color — ships in two boxes, about 17.4 lb (7.9 kg) each

Shipping note: the blocks arrive vacuum-compressed for safe transport. After unpacking, the foam needs up to 24 hours to fully expand and reach its final shape.

Building blocks kids love.

Read all reviews
Customer video review 1
★★★★★

Great building blocks! What I particularly love: they are washable. If you lay them out flat to dry, they regain their shape perfectly. We have the 48-piece set and build huge caves where several children can fit inside.

— Family H.
★★★★★

We could throw out every other toy we own and my kids would still be happy because all they want to do is play with their RIWIs! It promotes imagination enormously — everything from caves to entire castles is possible.

— Lauren M.
Customer video review 2
★★★★★

By far the best investment for indoor play. These blocks are functional, well-made, and allow kids to tumble and climb safely without any hard edges. Finally, a solution that keeps them active and safe at the same time!

— Mary H.
★★★★★

Radiant children's eyes and huge building fun! The material is soft, light, and grippy — perfect for stacking. A highlight is letting a tower fall over together and landing softly in a mountain of blocks. Odorless and high quality!

— Philipp
Customer video review 3
★★★★★

Just purchased my second set. There are many companies out there — but buy the original. The quality, versatility, and the fact that it still looks great in our living room makes it worth every penny. Absolute recommendation!

— Tamara H.
★★★★★

Our three children are always coming up with new ideas and love to throw themselves into their work at the end to destroy everything. Every kid builds their own thing — and the clean-up is quick because the blocks are so light.

— Benjamin
Which set is right for us?

Find your perfect RIWI® set.

All sets are compatible — start small and grow any time. More blocks, bigger builds.

12-block tower build
12 Blocks

Starter Set

Perfect for
1 child · small space · perfect gift
What you can build
Rockets, small forts, first towers
$159.95
$13.32 per block
#1 best seller
24-block walk-in cave
24 Blocks

Family Set

Perfect for
1–3 kids · living room · daily play
What you can build
Walk-in cave, giant tower, castle fort
$279.95$299.95
Now $11.66 / block
★ Best value
36-block house with roof
36 Blocks

Giant Set

Perfect for
2–4 kids · large playroom · siblings
What you can build
House with roof, spaceship, obstacle course
$359.95$399.95
Now $9.99 / block
Best for groups & daycare
48-block giant ship
48 Blocks

Mega Set

Perfect for
4+ kids · playgroup · daycare
What you can build
Giant ship, full city, mega obstacle course
$479.95$499.95
Now $9.99 / block

💡 Our #1 pick for most homes: the 24-Block Family Set — big enough for real forts and towers, easy to store when playtime's over. For playgroups, daycares and larger spaces, the 48-Block Mega Set is the move.

The best alternative to the screen is a better offer.
Real play“Less watching. More building.”

The best alternative to the screen is a better offer.

We're not anti-screen. We're pro what happens when it's off. Kids don't need another rule — they need something they actually want to do instead.

Building, moving, testing ideas, starting over: real play that holds their attention on its own.

  • Active play — building, climbing, tumbling
  • Open-ended: something new every time
  • Absorbing enough that nobody asks for the tablet
Why RIWI® exists

Built from a childhood dream.

Two friends. One memory. Towers to the ceiling. The floor is lava. Building forts and disappearing inside for hours — no instructions, no batteries, no end. That was the best toy of our childhood. And it didn't exist in stores.

Today's kids get toys with instructions, fixed rules and one right answer. Creativity on demand. Play by the manual. We missed that effortless freedom — so we built the toy we always wished we'd had.

That's RIWI®. #RaisingBuilders

RIWI® founders Roland (left) and Nicola (right) next to a RIWI block tower

Roland & Nicola — founded RIWI® in 2017

All reviews

What some of our 85,000+ parents say.

Over 95% of surveyed families say RIWI® is their kids’ favorite toy.

Goes with it

Complete the setup

Special combo offer — save 20% on the Couch Kit
24 Giant Building Blocks 24 Giant Building Blocks Build anything
2-in-1 Play Couch & Storage Kit 2-in-1 Play Couch & Storage Kit Build it, then chill on it

By day it's a fort, a tunnel, a ship. By evening, the same blocks become the comfiest seat in the house.

Play. Build. Chill.

The Play & Chill Combo

One set that builds everything — plus the cover kit that turns it into a couch and stores it away. The combo our families start with.

  • 24 Giant Building Blocks$279.95
  • 2-in-1 Play Couch & Storage Kitfrom $139.95
Combo price$391.91
$419.90 Save $27.99

Free shipping (USPS Ground) over $99 · washable covers

Different ages. Different ideas. Same blocks.
One set, every kid“One set. Every age. Every day.”

Different ages. Different ideas. Same blocks.

The four-year-old builds a cave. The eight-year-old engineers a bridge. Nobody fights over whose toy it is — because it's whatever they say it is.

One purchase that makes sense for the whole family, for years.

  • Grows with every kid from 3 to 10+
  • Siblings build together — or side by side
  • Replaces the pile of single-purpose toys
A moment to yourself is part of the plan.
For you, too“While they build, you get a minute.”

A moment to yourself is part of the plan.

When kids are deep in a build, they're absorbed — not entertained, absorbed. That's when the coffee stays hot, the book gets read, the bath actually happens.

Not as a reward. As part of the plan.

  • Independent play kids start on their own
  • Soft, light blocks they can carry and stack themselves
  • Quiet material — no crashing, no beeping
Why RIWI®?

What makes RIWI® different.

🏗️

Real walk-in builds

Kids build actual forts and caves big enough to crawl inside. No other home toy does this.

📵

Less screen time

When RIWI® comes out, the tablet disappears. Every. Single. Time.

📅

Played daily — for years

Not the toy that ends up in the corner after a week. RIWI® grows with your child.

🇪🇺

Made in Europe · TÜV Austria certified

Our own European factory. Tested to ASTM F963. Holds 242 lb. Machine-washable. Built to last.

🎨

No rules, no blueprint

Pure imagination every time — because there's no instruction manual for fun.

👨‍👩‍👧

The whole family plays

Parents get in on the action too — real quality time away from screens.

Good to know

Frequently asked questions

Ages 3 and up. The blocks are light enough for three-year-olds to carry and stack on their own, and open enough to stay interesting past age 10.

Yes — tested to ASTM F963 by an accredited lab, and TÜV Austria tested to EN 71. Soft PUR foam, no hard edges.

They stack freely — shape, size and material give builds a stable hold while staying quick to rebuild. No instructions, no connectors, no one right answer.

Each block supports up to 242 lb (110 kg) — so the couch build carries you for story time, too.

Compressed, from our U.S. warehouse. Free shipping (USPS Ground) on orders over $99. Blocks regain their full shape after unpacking.

The blocks are washable at 86 °F (30 °C) and dried flat — and the Velours and Play-Couch covers are machine-washable.

Set the stage. Then step back.

One open set. Every age from 3 up. Built by 85,000+ families in 30+ countries.

  • Free shipping $99+
  • Tested to ASTM F963
  • TÜV Austria EN 71
  • Made in Europe
  • 30-day returns
Choose your set