High-volume, cost-sensitive work
Choose Grok 4.20 Multi-Agent
Grok 4.20 Multi-Agent costs 22% less on a typical mix of three input tokens for every output token ($1.56 against $2.00 per million tokens).
GPT-6.1 Terra vs Grok 4.20 Multi-Agent: price, context and capabilities
Choose GPT-6.1 Terra for reused prompts and documents (RAG, agents) and the latest release. Choose Grok 4.20 Multi-Agent for high-volume, cost-sensitive work and writing and code generation.
In short
- Grok 4.20 Multi-Agent is 22% cheaper than GPT-6.1 Terra at the headline price ($1.56 / 1M tokens vs $2.00 / 1M tokens).
- GPT-6.1 Terra reads more per request: 1.05M tokens against 1M.
- GPT-6.1 Terra is the newer model (Oct 26, 2026, against March 2026).
- Only Grok 4.20 Multi-Agent offers batch api.
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Writing and code generation
Choose Grok 4.20 Multi-Agent
Grok 4.20 Multi-Agent charges $2.50 per million output tokens, against $5.00 for GPT-6.1 Terra. Output dominates the bill when answers are long.
Reused prompts and documents (RAG, agents)
Choose GPT-6.1 Terra
GPT-6.1 Terra charges $0.05 per million cached input tokens, against $0.20 for Grok 4.20 Multi-Agent.
Latest release
Choose GPT-6.1 Terra
GPT-6.1 Terra is the newer release (Oct 26, 2026, against March 2026 for Grok 4.20 Multi-Agent).
Monthly cost at three volumes
| Volume | GPT-6.1 Terra | Grok 4.20 Multi-Agent | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $2.25 | $1.88 | Grok 4.20 Multi-Agent, $0.38 less |
| Production: 20M input, 5M output tokens | $45.00 | $37.50 | Grok 4.20 Multi-Agent, $7.50 less |
| Scale: 500M input, 100M output tokens | $1,000 | $875.00 | Grok 4.20 Multi-Agent, $125.00 less |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| GPT-6.1 Terra | Grok 4.20 Multi-Agent | |
|---|---|---|
| Provider | OpenAI | xAI |
| Category | Language models | Language models |
| Status | Generally available | Generally available |
| Headline price | $2.00 / 1M tokens | $1.56 / 1M tokens |
| Input | $1.00 / 1M tokens | $1.25 / 1M tokens |
| Output | $5.00 / 1M tokens | $2.50 / 1M tokens |
| Cached input | $0.05 / 1M tokens | $0.20 / 1M tokens |
| Context window | 1.05M | 1M |
| Max output | 128k | No data |
| Released | Oct 26, 2026 | March 2026 |
| Knowledge cutoff | No data | No data |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API |
| API model id | gpt-6.1-terra | grok-4.20-multi-agent-0309 |
Frequently asked questions
Should I choose GPT-6.1 Terra or Grok 4.20 Multi-Agent?
Choose GPT-6.1 Terra for reused prompts and documents (RAG, agents) and the latest release. Choose Grok 4.20 Multi-Agent for high-volume, cost-sensitive work and writing and code generation.
Which is cheaper, GPT-6.1 Terra or Grok 4.20 Multi-Agent?
Grok 4.20 Multi-Agent is 22% cheaper than GPT-6.1 Terra at the headline price ($1.56 / 1M tokens vs $2.00 / 1M tokens).
Which has the larger context window, GPT-6.1 Terra or Grok 4.20 Multi-Agent?
GPT-6.1 Terra reads more per request: 1.05M tokens against 1M.
What is the difference between GPT-6.1 Terra and Grok 4.20 Multi-Agent?
GPT-6.1 Terra is made by OpenAI and Grok 4.20 Multi-Agent by xAI. Grok 4.20 Multi-Agent is 22% cheaper than GPT-6.1 Terra at the headline price ($1.56 / 1M tokens vs $2.00 / 1M tokens). GPT-6.1 Terra reads more per request: 1.05M tokens against 1M. GPT-6.1 Terra is the newer model (Oct 26, 2026, against March 2026). Only Grok 4.20 Multi-Agent offers batch api.
How much do GPT-6.1 Terra and Grok 4.20 Multi-Agent cost per month?
At 20 million input and 5 million output tokens a month, GPT-6.1 Terra costs $45.00 and Grok 4.20 Multi-Agent costs $37.50, at standard rates.
Which is newer, GPT-6.1 Terra or Grok 4.20 Multi-Agent?
GPT-6.1 Terra was released on Oct 26, 2026 and Grok 4.20 Multi-Agent on March 2026.