head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Optimization · Pure Optimization
A first-person factory builder that is pure logistics optimization.

Optimization · Pure Optimization
A hardcore programming-in-disguise puzzle where you wire atomic assembly lines to synthesize compounds.
Satisfactory leans Optimization (Pure Optimization); SpaceChem leans Optimization (Pure Optimization).
SpaceChem leans a little harder on execution, though the gap is small.
Satisfactory
Light platforming, no real mechanical ceiling.
SpaceChem
Drawing waldo paths requires no physical precision
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Satisfactory
No adaptive opponent in the world.
SpaceChem
No opponent; pure logic construction
Satisfactory leans a little harder on variance, though the gap is small.
Satisfactory
Resource nodes are fixed once mapped.
SpaceChem
All reactor inputs are deterministic and fixed
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Satisfactory
Ratios, logistics, and factory layout are everything.
SpaceChem
Designing correct chemical pipelines that transform inputs to outputs exactly
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.