OnePlus 12 vs Galaxy S21 Ultra: Size & Dimensions Compared
The OnePlus 12 and Galaxy S21 Ultra are nearly the same size, differing by just 0.8mm in height and 0.2mm in width.
Visual Size Overlay
OnePlus 12Galaxy S21 Ultra
Height Δ
-0.8mm
Width Δ
+0.2mm
Thickness Δ
+0.3mm
Case CompatibilityWon't Fit
- •Body dimensions are nearly identical, but the camera cutout is incompatible (circular-triple vs vertical-quad)
Screen ProtectorCompatible
Same screen size (6.8") with minimal width difference — should fit.
| Dimension | OnePlus 12 | Galaxy S21 Ultra | Difference |
|---|---|---|---|
| Height | 164.3mm | 165.1mm | Galaxy S21 Ultra +0.8mm (taller) |
| Width | 75.8mm | 75.6mm | Galaxy S21 Ultra -0.2mm (narrower) |
| Thickness | 9.2mm | 8.9mm | Galaxy S21 Ultra -0.3mm (thinner) |
| Weight | 220g | 227g | Galaxy S21 Ultra +7.0g (heavier) |
| Screen | 6.82" | 6.8" | Same |
Visual Size Comparison
HeightGalaxy S21 Ultra +0.8mm
OnePlus 12
164.3mm
Galaxy S21 Ultra
165.1mm
WidthOnePlus 12 +0.2mm
OnePlus 12
75.8mm
Galaxy S21 Ultra
75.6mm
ThicknessOnePlus 12 +0.3mm
OnePlus 12
9.2mm
Galaxy S21 Ultra
8.9mm
Button & Port Layout
Which is bigger?
The OnePlus 12 and Galaxy S21 Ultra are essentially the same size.
Wireless Charging & MagSafe Compatibility
Wireless chargers work with both phones, but magnetic snap varies.
- ✓Both devices support wireless charging. Standard Qi/Qi2 chargers work with either phone.
| Spec | OnePlus 12 | Galaxy S21 Ultra |
|---|---|---|
| Wireless Charging | 15W | 15W |
| Qi Version | Qi | Qi |
| MagSafe | No | No |
| Built-in Magnets | No | No |
MagSafe cases are NOT cross-compatible between these devices — the case body is shaped to each phone, even though the internal magnet ring may be the same.
Accessories for OnePlus 12
Spigen
Spigen Tough Armor for OnePlus 12
$17.99
Ringke
Ringke Fusion-X MagSafe for OnePlus 12
$14.99
Ringke
Ringke Fusion-X for OnePlus 12
$12.99
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Will a OnePlus 12 case fit Galaxy S21 Ultra? →Will a OnePlus 12 screen protector fit Galaxy S21 Ultra? →
Frequently Asked Questions
Is OnePlus 12 bigger than Galaxy S21 Ultra?
No, the Galaxy S21 Ultra is 0.8mm taller. The OnePlus 12 weighs 220g vs 227g.
Are OnePlus 12 and Galaxy S21 Ultra the same size?
Very close — they differ by only 0.8mm in height and 0.2mm in width.