Encode & Convert
10 tools
Converters and validators for Base64, JWT, hashes, QR codes, URL encoding, and related formats. Helpful for API work, shareable data, and specification checks.
How to choose a tool
Start with the tool closest to your task, then use the related tools near the bottom of each page when the workflow continues. Each tool page includes features, usage steps, and FAQs so users can understand what the tool does before relying on the result.
Encode & Convert
Base64 Encoder
Encode/decode strings and images to/from Base64.
JWT Decoder
Parse and display JWT token headers and payloads.
Hash Generator
Generate MD5/SHA-1/SHA-256 hash values.
QR Code Generator
Generate QR codes from text or URLs. Resizable, PNG export.
Aspect Ratio Calculator
Calculate aspect ratio from width and height. Reverse resize calculation.
Color Scheme Generator
Auto-generate complementary, analogous, triadic, and other color schemes.
Device Mockup
Composite screenshots with smartphone and PC device frames.
IP Subnet Calculator
Calculate network address, subnet mask, and host count.
UUID Generator
Generate UUID v4 and v7 in bulk. Toggle hyphens and case.
URLエンコード・デコード
URLエンコード・パーセントエンコード相互変換。