GPT-5 nano vs Grok 4.3
GPT-5 nano vs Grok 4.3: GPT-5 nano is cheaper for input-heavy usage ($0.05/M vs $1.25/M input tokens), while Grok 4.3 is better for long-context tasks (1,000,000 tokens).
Direct answer: choose GPT-5 nano for lower token spend and choose Grok 4.3 when your workload needs longer context.
Compare input and output token pricing, context windows, and monthly cost estimates on one page so you can pick the cheaper model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
GPT-5 nano
Grok 4.3
Cost Differences
Grok 4.3 costs more than GPT-5 nano
Quick Recommendation
Winner for direct API pricing: GPT-5 nano. At the default workload, GPT-5 nano saves about $6.75/month ($82.125/year) versus Grok 4.3.
Feature Comparison
| Feature | GPT-5 nano | Grok 4.3 |
|---|---|---|
| Provider | OpenAI | xAI |
| Input Price | $0.05/1M tokens | $1.25/1M tokens |
| Output Price | $0.40/1M tokens | $2.50/1M tokens |
| Context Window | 128,000 tokens | 1,000,000 tokens |
| Max Output | 8,192 tokens | 131,072 tokens |
| Category | efficient | reasoning |
| Capabilities | text | textvisionreasoning |
| Release Date | 8/7/2025 | 4/30/2026 |
GPT-5 nano vs Grok 4.3: Which Should You Choose?
Choosing between GPT-5 nano and Grok 4.3 depends on your priorities: cost efficiency, context length, or raw capability. GPT-5 nano is the more affordable option at $0.05/1M input tokens — 96% cheaper than Grok 4.3. Meanwhile, Grok 4.3 offers a significantly larger context window at 1,000,000 tokens vs 128,000 for GPT-5 nano.
These models come from different providers — OpenAI and xAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with OpenAI, switching to xAIinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
These models target different tiers: GPT-5 nano is a efficient model while Grok 4.3 is reasoning. This means they're optimized for different workloads. Grok 4.3 targets more demanding workloads, while GPT-5 nano provides a cost-effective option for everyday tasks.
Output costs matter too. GPT-5 nano charges $0.40/1M output tokens vs $2.50 for Grok 4.3. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. GPT-5 nano has the edge here at $0.40/1M output tokens.
Multimodal capabilities: Grok 4.3 supports vision (image inputs) while GPT-5 nano is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose GPT-5 nano when:
- • Budget is a primary concern
- • You're already using OpenAI's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Choose Grok 4.3 when:
- • You need a larger context window (1,000,000 tokens)
- • You need more capabilities (vision, reasoning)
- • You need longer outputs (up to 131,072 tokens)
- • You're already using xAI's API ecosystem
Pros and Caveats at a Glance
GPT-5 nano
- • Input pricing: $0.05/M tokens
- • Output pricing: $0.40/M tokens
- • Context window: 128,000 tokens
- • Max output: 8,192 tokens
Watch out for
- • Smaller context window than Grok 4.3
Grok 4.3
- • Input pricing: $1.25/M tokens
- • Output pricing: $2.50/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 131,072 tokens
Watch out for
- • Higher input cost than GPT-5 nano
- • Higher output cost than GPT-5 nano
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
GPT-5 nano (OpenAI)
Grok 4.3 (xAI)
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Sign Up for xAI →Frequently Asked Questions
Which is cheaper, GPT-5 nano or Grok 4.3?▼
What is the context window difference between GPT-5 nano and Grok 4.3?▼
Which model is better for AI Chatbot?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare OpenAI and xAI API pricing beyond this model matchup?▼
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