ここでは、各 Webブラウザにおける JavaScriptのバージョンの実装状態について一覧表にしてまとめました。
| MSIE (Mac) |
MSIE (Win) | Netscape | Mozilla | Opera | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Version | 4.5 | 5.2 | 3.0 | 4.0 | 5.0 | 5.5 | 6.0 | 2.0 | 3.0 | 4.0- 4.05 |
4.06 -4.7 | 6.0 | 7.0 | 1.0 | 6.0 | 7.03 | |
| JavaScript 2.0 | × | × | × | × | × | × | × | × | × | × | × | × | × | × | × | × | |
| JavaScript 1.6 | × | × | × | × | × | × | × | × | × | × | × | × | × | × | × | × | |
| JavaScript 1.5 | × | × | × | × | × | × | × | × | × | × | × | 〇 | 〇 | 〇 | × | × | |
| JavaScript 1.4 | × | 〇 | × | × | × | × | × | × | × | × | × | 〇 | 〇 | 〇 | 〇 | 〇 | |
| JavaScript 1.3 | × | 〇 | × | × | 〇 | 〇 | 〇 | × | × | × | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | |
| JavaScript 1.2 | × | 〇 | 〇 | × | 〇 | 〇 | 〇 | × | × | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | |
| JavaScript 1.1 | × | 〇 | 〇 | × | 〇 | 〇 | 〇 | × | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | |
| JavaScript 1.0 | × | ○ | △ | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | 〇 | |