RosettaScript
A GridBridge Labs Tool
Pro is live Pricing LSL → SLua History gridbridgelabs.com ↗
GDScript 3 → GDScript 4 Converter

Migrate your scripts.
Godot 3 syntax, Godot 4 output.

The automatic GDScript 3→4 converter for Godot. Free mechanical conversion for any script. AI-refined Pro tier that handles Tween, File→FileAccess, KinematicBody→CharacterBody, and semantic rewrites Godot's built-in converter misses — explained line-by-line.

◈  Paste your GDScript 3
GDScript 4 Output  ◈
GDScript 3 Editable — paste your script
GDScript 4 Converted output 

      

    

  

  

  

    
Click  Convert  to run the free Tier 1 transpiler

  

  

  
  

    Your output
    
    
    
  





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See what Pro produces.

    
Tier 1 gives you syntax-correct GDScript 4 that runs. Pro sends the original GDScript 3 + Tier 1 output to Claude, which refactors to idiomatic Godot 4 and explains every change. Below: a real capture from our player.gd test fixture.

  

  

    

      

        Tier 1 · Mechanical
        18 lines · syntax-correct
      

      

    

    

      

        Tier 2 · Claude-refined
        15 lines · 3 refinements
      

      

    

  

  

    

      
line 9

      

        
Typed const SPEED := 200.0 with inferred float literal.

        
GDScript 4 prefers typed constants. Making SPEED explicitly a float avoids integer math surprises when multiplying Vector2.

      

    

    

      
line 11

      

        
Added explicit type hints: func _physics_process(delta: float) -> void.

        
Godot 4's static analyzer catches misuse at compile time when types are declared. Idiomatic 4.x style.

      

    

    

      
line 18

      

        
Replaced velocity = move_and_slide(velocity, Vector2.UP) with move_and_slide().

        
CharacterBody2D exposes velocity as a built-in property and up_direction is set via the export, so move_and_slide() takes no arguments in Godot 4.

      

    

  

  

    Try Pro with your own script →
  





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Simple pricing.

    
Mechanical conversion is free forever. Pro tier unlocks Claude refinement with explanations — pay per conversion or go unlimited. Credits work on both Godot and LSL conversions.

  

  

    

      
Free No account

      
Free · forever

      
Try it above. No signup.

      
    
        
  • Mechanical syntax conversion
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  • Unlimited scripts
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  • KinematicBody → CharacterBody
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  • move_and_slide / is_on_floor updates
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  • Manual-review flags for risky patterns
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Single Pay as you go

      
$2 · one-time

      
L$500 · 1 conversion

      
    
        
  • One Claude-refined conversion
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  • Idiomatic GDScript 4 output
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  • Line-by-line explanations
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  • Tween / FileAccess rewrites
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  • Typed variables + return hints
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10-Pack Best value

      
$12 · one-time

      
L$3,000 · $1.20 each

      
    
        
  • 10 Claude-refined conversions
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  • 40% off the single-conversion price
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  • Credits never expire
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  • Works on Godot + LSL both
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50-Pack Power user

      
$40 · one-time

      
L$10,000 · $0.80 each

      
    
        
  • 50 Claude-refined conversions
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  • 60% off the single-conversion price
    • 
        
  • Credits never expire
    • 
        
  • Works on Godot + LSL both
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Unlimited Monthly

      
$20 / month

      
L$5,000/mo · Cancel anytime

      
    
        
  • Unlimited Claude-refined conversions
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  • For heavy-conversion months
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  • Works on Godot + LSL both
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  • Cancel from the Stripe portal
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Key transformations.

  
A quick reference for what the free Tier 1 transpiler handles automatically.

  

    
KinematicBody2D
→
CharacterBody2DPhysics bodies

    
move_and_slide(v, UP)
→
move_and_slide()Built-in velocity

    
Tween.new()
→
create_tween()SceneTreeTween

    
yield(sig, "name")
→
await sig.nameAwait signals

    
File.new()
→
FileAccess.open()File I/O

    
onready var x
→
@onready var xAnnotations

    
export(int) var x
→
@export var x: intTyped exports

    
connect("s", self, "m")
→
s.connect(m)Signal connect

    
func _ready():
→
func _ready() -> void:Type hints