When to Use Map vs Object
When to Use Map vs Object
Section titled “When to Use Map vs Object”Use Map when:
Section titled “Use Map when:”- keys are not strings
- need guaranteed insertion order
- frequent additions/deletions
- want better performance semantics
Use Object when:
Section titled “Use Object when:”- simple JSON-like data
- keys are strings only
| Feature | Object | Map |
|---|---|---|
| Key types | Strings or Symbols | Any type (objects, numbers, functions, etc.) |
| Order preserved | ❌ Not guaranteed (older JS) | ✅ Preserves insertion order |
| Size property | ❌ No direct property (Object.keys().length) | ✅ map.size |
| Performance | Good for small data | Better for large datasets |
| Iteration | Less clean (for...in, Object.keys) | Cleaner (for...of, map.forEach) |