GPT-5.3 Codex vs Granite-4.0-H-1B

Pick GPT-5.3 Codex if you want the stronger benchmark profile. Granite-4.0-H-1B only becomes the better choice if you want the cheaper token bill or you would rather avoid the extra latency and token burn of a reasoning model.

GPT-5.3 Codex is clearly ahead on the aggregate, 85 to 43. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.3 Codex's sharpest advantage is in multilingual, where it averages 92.8 against 37.8. The single biggest benchmark swing on the page is MGSM, 96% to 37.8%.

GPT-5.3 Codex is also the more expensive model on tokens at $2.50 input / $10.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Granite-4.0-H-1B. That is roughly Infinityx on output cost alone. GPT-5.3 Codex is the reasoning model in the pair, while Granite-4.0-H-1B is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. GPT-5.3 Codex gives you the larger context window at 400K, compared with 128K for Granite-4.0-H-1B.