Surface Current Density Converter

Ampere/square meter (A/m²)

The SI unit of surface current density, representing the amount of electric current per unit surface area. 1 A/m² = 0.0001 A/cm².

Common uses: PCB traces, thin film conductivity, electroplating, semiconductor surface analysis.

Ampere/square centimeter (A/cm²)

CGS unit of surface current density. 1 A/cm² = 10,000 A/m². Widely used in electrochemistry and materials science.

Common uses: Corrosion rates, electroplating specifications, battery electrode analysis.

Ampere/square inch (A/in²)

Imperial unit of surface current density. 1 A/in² ≈ 1550 A/m². Used in North American industrial applications.

Common uses: Wire gauges, industrial conductor specifications, electrical equipment ratings.

Ampere/square mil (A/mil²)

Sub-imperial unit used in precise electrical specifications. 1 A/mil² ≈ 1.55 × 10⁸ A/m².

Application: Very precise wire sizing, microelectronics, and aerospace specifications.

Ampere/circular mil (A/cmil)

Specialized unit used for wire current capacity ratings. Based on circular mil wire cross-sections. 1 A/cmil ≈ 1.973 × 10⁸ A/m².

Application: Wire ampacity tables, electrical codes, conductor sizing standards (NEC/AWG).

Abampere/square centimeter (abA/cm²)

CGS electromagnetic unit of surface current density. 1 abA/cm² = 10,000 A/cm². Part of the CGS-emu system.

Application: Legacy scientific measurements, historical electromagnetic calculations.

Surface Current Density Context

• Typical PCB trace: 1-10 A/cm² (10,000-100,000 A/m²)
• Plating applications: 0.1-5 A/dm² for electroplating
• Wire ampacity: 50-100 A/cmil for copper at safe operating temperature
• Corrosion current: Typically 10⁻⁶ to 10⁻¹ A/cm² depending on material
• Battery electrodes: 0.1-1 A/cm² for typical li-ion cells
• Superconductors: Can carry 10⁵+ A/cm² in critical state