Question 1

How do I convert hexadecimal to decimal manually?

Accepted Answer

Multiply each hex digit by 16 raised to its positional power and sum the results. Letters A–F equal 10–15. Example: 0xFF = (15×16¹) + (15×16⁰) = 240 + 15 = 255. Example: 0x1A3 = (1×256) + (10×16) + (3×1) = 256 + 160 + 3 = 419.

Question 2

Are hex numbers case-sensitive?

Accepted Answer

No. 0xFF and 0XFF and ff all represent the same value. By convention, uppercase A–F is common in addresses and machine code; lowercase a–f is common in color codes (#ff5733) and hash digests. This tool accepts both.

Question 3

What is the largest 2-digit hex number in decimal?

Accepted Answer

FF hex = 255 decimal (the maximum value of one byte). This is why byte values span 0–255 and color channels in RGB go from 0 to 255. A single byte can be expressed exactly as two hex digits (00–FF).

16進→10進

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