GPT-5 Codex vs Grok 4.20 Multi-Agent
A side-by-side comparison of two multimodal models — real specs, pricing, strengths and weaknesses, and a clear verdict on which to choose. Kept current by our agents.
Quick verdict: which should you choose?
Choose GPT-5 Codex if you need
- ✓Strong coding specialization with unified text and image reasoning
- ✓Documented intelligence index of 44.6 and output speed of 149.9 t/s
- ✓Effective handling of extremely large inputs up to 400k context
- ✓Scenarios where coherence in long outputs is prioritized over multi-agent coordination
Choose Grok 4.20 Multi-Agent if you need
- ✓Extremely long contexts up to 2M tokens for massive inputs
- ✓Lower price at $6 per million tokens and native handling of text, images, and files
- ✓Multi-agent coordination for complex workflows
- ✓Tasks where file support and agent orchestration outweigh single-model speed
Verdict
Grok 4.20 Multi-Agent leads on context length and price while GPT-5 Codex leads on documented intelligence, output speed, and coding specialization. GPT-5 Codex offers unified text-image reasoning with a known 44.6 intelligence index and 149.9 t/s speed at $10 per million tokens. Grok 4.20 Multi-Agent supports 2M context, native file handling, and multi-agent workflows at $6 per million tokens but lacks published intelligence or speed metrics.
GPT-5 Codex vs Grok 4.20 Multi-Agent: side by side
| Spec | GPT-5 Codex | Grok 4.20 Multi-Agent | Winner |
|---|---|---|---|
| Intelligence | 44.6 | — | Tie |
| Output speed | 150 t/s | — | Tie |
| Output price | $10.00/1M | $6.00/1M | Grok 4.20 Multi-Agent |
| Context | 400K | 2000K | Grok 4.20 Multi-Agent |
| Params | — | — | Tie |
| Type | Proprietary | Proprietary | Tie |
| Provider | OpenAI | xAI | Tie |
Detailed analysis
Pricing
Winner: Grok 4.20 Multi-AgentGrok 4.20 Multi-Agent costs $6 per million tokens compared to GPT-5 Codex at $10 per million tokens. Both are proprietary models from their respective providers. This gives Grok a clear cost advantage for high-volume usage.
Context Length
Winner: Grok 4.20 Multi-AgentGrok 4.20 Multi-Agent supports 2,000,000 context tokens versus GPT-5 Codex at 400,000. Grok's strength explicitly includes extremely long contexts and multi-agent workflows. GPT-5 Codex notes high resource demands at its maximum context size.
Performance Metrics
Winner: GPT-5 CodexGPT-5 Codex provides an intelligence index of 44.6 and output speed of 149.9 t/s while Grok 4.20 Multi-Agent has no published values for either. GPT-5 Codex also emphasizes strong coding specialization and unified text-image reasoning. Grok focuses on agent coordination which may add latency.
Modalities & Features
Winner: TieGPT-5 Codex handles text and static images with unified reasoning but is limited to those. Grok 4.20 Multi-Agent handles text, images, and files natively with multi-agent support yet excludes audio or video. Each covers distinct multimodal strengths without full overlap.
GPT-5 Codex
Pros
- +Handles extremely large inputs effectively
- +Strong coding specialization
- +Unified text and image reasoning
Cons
- –High resource demands with maximum context
- –Limited to text and static images
- –Potential coherence loss in very long outputs
Grok 4.20 Multi-Agent
Pros
- +Supports extremely long contexts
- +Coordinates multiple agents for workflows
- +Handles text, images, and files natively
Cons
- –Multi-agent setups may add latency
- –Coordination overhead on simple tasks
- –No audio or video modalities
Summary: GPT-5 Codex vs Grok 4.20 Multi-Agent
Choose GPT-5 Codex when coding performance, known speed, and image-text reasoning matter most. Choose Grok 4.20 Multi-Agent when maximum context, lower cost, and multi-agent file workflows are required. The decision hinges on whether documented metrics or extended context and pricing take priority.
Frequently asked questions
GPT-5 Codex leads where intelligence, speed, and coding are measured while Grok 4.20 Multi-Agent leads on context size and price; neither is universally better.