Encode & Convert

Encode/decode strings and images to/from Base64.

Parse and display JWT token headers and payloads.

Generate MD5/SHA-1/SHA-256 hash values.

Generate QR codes from text or URLs. Resizable, PNG export.

Calculate aspect ratio from width and height. Reverse resize calculation.

Auto-generate complementary, analogous, triadic, and other color schemes.

Composite screenshots with smartphone and PC device frames.

Calculate network address, subnet mask, and host count.

UTF-8/Shift_JIS等の文字コード変換・バイト列表示。