About Adapter Guru
We believe finding out if a replacement power supply or charger is safe should take seconds, not hours of confusing forum research.
Instant Clarity
No engineering jargon or confusing equations. Just clear green, amber, and red safety evaluations with straightforward advice.
100% Private
All computations run directly in your browser. Zero tracking, zero telemetry, and zero user data sent to external servers.
Deterministic Precision
Calculations are backed by Ohm's Law, IEEE & EIAJ standards, and the NEC 80% continuous duty safety rule.
Why We Built Adapter Guru
Every home and office has a drawer full of mystery black power bricks. When an original adapter is lost or fails, consumers face a confusing array of numbers: "12V 1.5A", "19V 3.42A", "Center Positive ⊕", "5.5×2.1mm", and "USB-C 65W PD".
Plugging in the wrong adapter can fry an expensive gadget in milliseconds. Conversely, many people unnecessarily buy new power supplies when an existing brick in their drawer is completely safe to use.
Adapter Guru was created to give everyone—from students and homeowners to IT professionals and audio technicians—instant confidence before plugging in any power supply.
Know before you plug in
Safely check any power adapter against your electronic devices right now.
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