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42121 LEGO Technic Heavy Duty Excavator thumbnail image

42121 LEGO Technic Heavy Duty Excavator
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42121 LEGO Technic Heavy Duty Excavator
  • Heavy Duty Excavator thumbnail
  • Heavy Duty Excavator thumbnail
  • Heavy Duty Excavator thumbnail
  • Heavy Duty Excavator thumbnail
  • Heavy Duty Excavator thumbnail
  • Heavy Duty Excavator thumbnail

LEGO 42121 Heavy Duty Excavator is a Technic set valued at $130 for new and sealed sets, up 225% from an original retail price of $39.99. The set retired in November 2022 with annual appreciation averaging 16.57% since. On the used market, values range from $34 to $44 based on condition. Secondary market prices for new and sealed sets typically fall between $100 and $176. Signals for the set point upward at the moment, led by a value on the rise as well as growth ahead of similar sets.

Heavy Duty Excavator Value (New/Sealed)

This chart represents the current new/sealed value of the set Heavy Duty Excavator since November 2022. Very high accuracy
LEGO 42121 Heavy-Duty Excavator is a Technic set released in 2021, containing 569 pieces. It builds a tracked excavator with a movable boom, arm, and bucket, a rotating upper structure, and working tracks. The 2-in-1 model can be rebuilt into a tracked tractor with a backhoe.

Heavy Duty Excavator has climbed about 16.6% a year since retirement and is worth around $130 sealed. If the forecast is right, it keeps going, to about $145 in five years. The average used price is $36 for those in good overall condition. New and sealed listings currently range from $110 to $175. The set was available for 20 months, from March 2021 to November 2022.
All regions

For Sale (New/Sealed)

 (US) Technic 42121 Heavy-Duty Excavator 8+ 569pcs New Sealed Heavy Duty 2 In 1
BrickEconomy Choice
$89.99
(US) TECHNIC: Heavy-Duty Excavator (42121) $99.50
-23.5%
(US) 42121 TECHNIC Heavy-Duty Excavator | Retired | New & Sealed $99.99
-23.1%
(US) TECHNIC: Heavy-Duty Excavator (42121) $100.00
-23.1%
(US) TECHNIC HEAVY-DUTY EXCAVATOR 569 PCS 42121 NEW IN BOX 2021 RETIRED 2 IN ONE $103.76
-20.2%
(AU) Technic - Heavy Duty Excavator (or Tracked Tractor) 2-in-1 #42121 BNIB $104.95
-19.3%
(US) TECHNIC HEAVY-DUTY EXCAVATOR 569 PCS 42121 NEW IN BOX 2021 RETIRED $111.60
-14.1%
(US) Technic 42121 Heavy-Duty Excavator 8+ 569pcs New Sealed Heavy Duty 2 In 1 $119.00
-8.5%
(US) 42121 Technic Heavy Duty Excavator $120.00
-7.7%
(US) TECHNIC: Heavy-Duty Excavator (42121) $129.99
(US) TECHNIC: Heavy-Duty Excavator (42121) $134.99
+3.8%
(JP) 42121 TECHNIC: Heavy-Duty Excavator Block toy 8+ New $142.63
+9.7%
(US) Technic Heavy-Duty Excavator 42121 $147.83
+13.7%
(US) TECHNIC: Heavy-Duty Excavator (42121) $150.00
+15.4%
Picked for your regionShow 9 more listings

Sales Distribution (Last 90 Days)

This chart shows the distribution of sales for the past three months of new/sealed 42121 Heavy Duty Excavator.

Sale Trends

This chart shows the sales trends of new/sealed 42121 Heavy Duty Excavator.

Market Momentum

Bullish
This set's value is climbing and it is outpacing its theme.
DemandTop 9% in Technic
Very high demand but falling
12 months agoToday
SupplyMore than most in Technic
Listings down 32% this month
12 months agoToday
Growth vs peers+1% typical for Technic
+44% over the past year
12 months agoToday
Outlook:7% bearish·13% neutral·80% bullish
Why it's moving, signals and outlook

Compared with other Technic Excavator sets

Given that similar sets have not kept pace with Heavy Duty Excavator over the past year and that it began at a lower retail price than most sets below it, it is no surprise that it sits in the middle of the Technic Excavator sets.

#6 of 10
By growth since retail, +225%
+79%+898%
In the bottom half of the group.
$0.23 a piece
New and sealed value per piece
This set
$0.23
Typical
$0.32
About 30% below the group's typical value per piece.
#4 of 10
Used value as a share of new, 28%
9%52%
In the top half of the group.
#6 of 10 retired
Wanted for each member who owns it
This set
Typical
Close to the rate of the group's retired sets.
Technic Excavator sets by valueValueSince retail
8043 Motorized Excavator$620+210%
42055 Bucket Wheel Excavator$500+79%
8851 Excavator$459+898%
8853 Excavator$200+524%
42006 Excavator$183+129%
8294 Excavator$171+185%
8837 Pneumatic Excavator$158+237%
42121 Heavy Duty Excavator$130+225%

Technic Excavator Sets

42055 Bucket Wheel Excavator

Theme Technic
Year 2016
Pieces 3,927
Availability Retired
42055 LEGO Technic Bucket Wheel Excavator
Retail $279.99
Value $500.01
Growth  +78.6%
Annual growth 8.4%

42006 Excavator

Theme Technic
Year 2013
Pieces 720
Availability Retired
42006 LEGO Technic Excavator
Retail $79.99
Value $183.13
Growth  +128.9%
Annual growth 3.5%

8043 Motorized Excavator

Theme Technic
Year 2010
Pieces 1,123
Availability Retired
8043 LEGO Technic Motorized Excavator
Retail $199.99
Value $619.98
Growth  +210.0%
Annual growth 8.4%

8047 Compact Excavator

Theme Technic
Year 2010
Pieces 252
Availability Retired
8047 LEGO Technic Compact Excavator
Retail $24.99
Value $84.12
Growth  +236.6%
Annual growth 5.4%

8294 Excavator

Theme Technic
Year 2008
Pieces 720
Availability Retired
8294 LEGO Technic Excavator
Retail $59.99
Value $171.25
Growth  +185.5%
Annual growth 5.0%

8419 Excavator

Theme Technic
Year 2005
Pieces 286
Availability Retired
8419 LEGO Technic Excavator
Retail $19.99
Value $89.13
Growth  +345.9%
Annual growth 8.0%

8837 Pneumatic Excavator

Theme Technic
Year 1992
Pieces 257
Availability Retired
8837 LEGO Technic Pneumatic Excavator
Retail $47.00
Value $158.45
Growth  +237.1%
Annual growth 3.4%

8853 Excavator

Theme Technic
Year 1988
Pieces 326
Availability Retired
8853 LEGO Technic Excavator
Retail $32.00
Value $199.68
Growth  +524.0%
Annual growth 4.9%

8851 Excavator

Theme Technic
Year 1984
Pieces 347
Availability Retired
8851 LEGO Technic Excavator
Retail $46.00
Value $459.18
Growth  +898.2%
Annual growth 3.0%

Sets in Technic

42131 Cat D11 Bulldozer

Theme Technic
Year 2021
Pieces 3,854
Availability Retired
42131 LEGO Technic Cat D11 Bulldozer
Retail $499.99
Value $895.76
Growth  +79.2%
Annual growth 15.2%

42128 Heavy-Duty Tow Truck

Theme Technic
Year 2021
Pieces 2,017
Availability Retired
42128 LEGO Technic Heavy-Duty Tow Truck
Retail $159.99
Value $264.46
Growth  +65.3%
Annual growth 20.7%

42126 Ford F-150 Raptor

Theme Technic
Year 2021
Pieces 1,379
Availability Retired
42126 LEGO Technic Ford F-150 Raptor
Retail $99.99
Value $277.36
Growth  +177.4%
Annual growth 29.6%

42122 Jeep Wrangler

Theme Technic
Year 2021
Pieces 665
Availability Retired
42122 LEGO Technic Jeep Wrangler
Retail $49.99
Value $58.07
Growth  +16.2%
Annual growth 5.8%

42120 Rescue Hovercraft

Theme Technic
Year 2021
Pieces 457
Availability Retired
42120 LEGO Technic Rescue Hovercraft
Retail $29.99
Value $55.00
Growth  +83.4%
Annual growth 10.2%

42124 Off-Road Buggy

Theme Technic
Year 2021
Pieces 374
Availability Retired
42124 LEGO Technic Off-Road Buggy
Retail $129.99
Value $195.47
Growth  +50.4%
Annual growth 9.4%

42117 Race Plane

Theme Technic
Year 2021
Pieces 145
Availability Retired
42117 LEGO Technic Race Plane
Retail $9.99
Value $25.71
Growth  +157.4%
Annual growth 24.7%

42116 Skid Steer Loader

Theme Technic
Year 2021
Pieces 140
Availability Retired
42116 LEGO Technic Skid Steer Loader
Retail $9.99
Value $22.00
Growth  +120.2%
Annual growth 15.7%

30465 Helicopter

Theme Technic
Year 2021
Pieces 70
Availability Retired
30465 LEGO Technic Helicopter
Retail $4.99
Value $12.29
Growth  +146.3%
Annual growth 10.4%

Heavy Duty Excavator Questions

How much is LEGO 42121 Heavy Duty Excavator worth today?

Today's value for a new, sealed copy of Heavy Duty Excavator is $130. Sealed copies typically change hands for $100 to $176. The value has risen 38% in the past 90 days. A used copy in good condition goes for about $36.

Is LEGO 42121 Heavy Duty Excavator retired?

Yes. Heavy Duty Excavator left LEGO's shelves in November 2022 after a run of 20 months. Collectors now buy it on the secondary market, from sellers on sites like eBay and BrickLink.

How much has LEGO 42121 Heavy Duty Excavator gone up in value?

Since it sold for $39.99 in shops, Heavy Duty Excavator has risen 225% in value, or roughly 16.6% a year on average. It has outgrown the Technic average of 4% a year by a clear margin.

What will LEGO 42121 Heavy Duty Excavator be worth next year?

In twelve months, Heavy Duty Excavator could be worth around $130, close to where it is today. In the short term the market reads bullish. Demand, supply and price signals are leaning upward. Like any forecast, this is an estimate.

How many pieces are in LEGO 42121 Heavy Duty Excavator?

The set contains 569 pieces, or $0.07 per piece at retail.

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My Collection

Heavy Duty Excavator Reviews

34 reviews
4.7
Collectors
Investors
Eurobricks
“I think this is a great set for its target market. This isn't meant to compete with the $100+ sets like the motorized 8043 or massive Bucket Wheel Excavator. This is a set kids will get and love. I particularly appreciate that the instructions start with building the arm and... More even call out to test the functionality before moving on to bag 2. That's a great user experience right there.”
Full review at www.eurobricks.com
Brickset
“It's a realistic and compact model that packs a good amount of functionality into its demure size. It works well and is likely to be fun to play with if you're the right age to do so. The arm looks a bit out of scale with the body to me, but it's not a deal-breaker.... More Unfortunately, the frosty windscreen mars what would otherwise be a pretty much perfect model.”
Full review at brickset.com
BrickFanatics
“It is smaller than expected, but that can be seen as a positive. It offers similar functionality to much larger vehicles of this type, but doesn't take up masses of space on the shelf. The finished model looks excellent, the digging feature is fun to use (once mastered) and... More it retails for a very respectable price. Overall, 42121 Heavy-Duty Excavator is a set we really… dig.”
Full review at www.brickfanatics.com

About Technic

TECHNIC is one of The LEGO Company's main lines based on creating detailed model machines and mechanical toys with specialized beams, axles, gears and connectors. The theme was first introduced as the Expert Builder series in 1977, but was officially renamed as TECHNIC in 1984.
Summary
Technic Heavy Duty Excavator set 42121 was released in March 2021, retailing for $40, but has since been retired. New, unopened Heavy Duty Excavator sets are valued at $130, while used sets can be found for $36.
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Looking for a special gift for kids who love construction toy sets? This 2-in-1 LEGO® Technic™ Heavy-Duty Excavator (42121) toy has plenty of features for hours of creative play. Boys and girls aged 8 and up will enjoy an immersive building challenge before exploring the digger toy's realistic features.

See how an excavator works
Digging, driving, rotating; there's so much to discover in this cool kids' excavator toy. Check out the shovel that moves up and down, plus the movable arm, running belts and rotating body. There’s also a detailed cabin with a driver’s seat and control panel. The set comes with extra LEGO brick ‘stones’ to dig and 4 cones. When it’s time for a new challenge, the model rebuilds into a tracked tractor with backhoe.

Packed with realistic features, this digger toy set lets kids see how construction vehicles really work. Check out the moving shovel and arm, plus running belts, just like on a real excavator.

When kids are ready for a new challenge, the...
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