Base64 Index Table (RFC 4648)
0–25: A–Z
26–51: a–z
52–61: 0–9
62 & 63: + and / (Std)
Standard vs URL-Safe Variant
| Feature | Standard Base64 | URL-Safe (Base64URL) |
|---|---|---|
| Index 62 | + | - (hyphen) |
| Index 63 | / | _ (underscore) |
| Padding (=) | Required for length % 4 == 0 | Omitted / Optional |
Common Data URI Prefixes
PNG Image: data:image/png;base64,iVBORw0KGgo...
JPEG Image: data:image/jpeg;base64,/9j/4AAQSkZJRg...
SVG Vector: data:image/svg+xml;base64,PHN2ZyB4bWxucz...
PDF Document: data:application/pdf;base64,JVBERi0xLjUN...
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