# Grok 4.20 (reasoning) vs Grok 4.7

Grok 4.7 is one of xAI's newest models and Grok 4.20 (reasoning) an earlier one, so this is also what moving up costs or saves. Grok 4.20 (reasoning) is the cheaper of the 2: for the same tokens, 3 read for each 1 written, Grok 4.7 costs 1.9 times as much. Below are both price lists, what 8 everyday jobs cost a month on each, and how many tokens the same text takes on each, which can change the answer.

- Page, with a calculator for your own job: https://tecyfy.com/prices/compare/grok-4-20-0309-reasoning-vs-grok-4-7
- Makers: Grok 4.20 (reasoning) from xAI, Grok 4.7 from xAI

## Price per million tokens, in US dollars

| | Grok 4.20 (reasoning) | Grok 4.7 |
| --- | --: | --: |
| Input | $1.25 | $2 |
| Cached input | $0.20 | $0.50 |
| Cache write | not listed | not listed |
| Output | $2.50 | $6 |
| Blend, 3 read for each 1 written | $1.5625 | $3 |
| Batch input | not listed | not listed |
| Batch output | not listed | not listed |
| Long prompt input (above 200K on Grok 4.20 (reasoning), 200K on Grok 4.7) | $2.50 | $4 |
| Long prompt output | $5 | $12 |
| Context window, tokens | 1M | 500K |
| Capability score (Epoch Capabilities Index; GPT-5 is 150) | not listed | 154 |
| Longest answer, tokens | not listed | not listed |

## What 8 everyday jobs cost a month on each

Each job at its usual runs a day, for 30 days, at the standard price.

| Job | Tokens in, out, runs a day | Grok 4.20 (reasoning) | Grok 4.7 |
| --- | --- | --: | --: |
| A chat question | 300, 500, 100 | $4.88 | $10.80 |
| A hard question, with thinking | 300, 1,400, 100 | $11.63 | $27.00 |
| A long report, summarised | 60,000, 2,000, 20 | $48.00 | $79.20 |
| A 40-turn agent task | 2,800,000, 40,000, 10 | $286 | $618 |
| A support bot's reply | 4,000, 300, 2,000 | $219 | $408 |
| Sort a message into a category | 250, 5, 50,000 | $488 | $795 |
| Read an invoice into fields | 1,500, 250, 1,000 | $75.00 | $135 |
| Review a pull request | 25,000, 4,500, 50 | $63.75 | $116 |

## Questions

### Which is cheaper, Grok 4.20 (reasoning) or Grok 4.7?

Grok 4.20 (reasoning) is cheaper: $1.25 per million tokens read and $2.50 per million written, against $2 and $6 on Grok 4.7. On a mix of 3 tokens read for each 1 written, Grok 4.7 costs 1.9 times as much.

### Which is better, Grok 4.20 (reasoning) or Grok 4.7?

Grok 4.7 scores 154 on the Epoch Capabilities Index, an independent score from Epoch AI that combines over 50 benchmarks (GPT-5 is 150). Grok 4.20 (reasoning) has no independent score yet, so the only fair test is to run the same 10 tasks on both.

### What does a support bot cost a month on Grok 4.20 (reasoning) and Grok 4.7?

At 2,000 replies a day, each reading 4,000 tokens (50 percent of them from cache) and writing 300, it costs $219 a month on Grok 4.20 (reasoning) and $408 on Grok 4.7: Grok 4.7 costs 1.9 times as much for this job.

### What does an AI agent task cost on Grok 4.20 (reasoning) and Grok 4.7?

One 40-turn task that reads 2,800,000 tokens in all, 90 percent of them from cache, and writes 40,000, costs 95 cents on Grok 4.20 (reasoning) and $2.06 on Grok 4.7. At 10 tasks a day that is $286 and $618 a month.

### Which has the larger context window, Grok 4.20 (reasoning) or Grok 4.7?

Grok 4.20 (reasoning), with 1M tokens against 500K on Grok 4.7. The window holds your instructions, the files you attach, the conversation so far and the answer, all at once.

### Does the same text take the same number of tokens on Grok 4.20 (reasoning) and Grok 4.7?

Yes, both are counted the same way: our lesson "How AI writes", 1,700 words long, is about 2,100 tokens on each.

### Is it cheaper to move from Grok 4.20 (reasoning) to Grok 4.7?

No, it costs more per token: Grok 4.7 charges $2 per million tokens read and $6 written, against $1.25 and $2.50 on Grok 4.20 (reasoning), 1.9 times as much for the same tokens. It pays off only if better answers save more than that, for example in fewer retries.

### Can I pay less on Grok 4.20 (reasoning) and Grok 4.7 for work that can wait?

Not with a batch price: neither maker's price page lists one for these models. A cache still lowers the price of text the model reads again.

## Sources

- [xAI: API prices](https://docs.x.ai/docs/models)
- [Epoch Capabilities Index, by Epoch AI (CC BY 4.0)](https://epoch.ai/benchmarks/eci)

## Other comparisons

- [Grok 4.6 vs Grok 4.7](https://tecyfy.com/prices/compare/grok-4-6-vs-grok-4-7.md)
- [Grok 4.5 vs Grok 4.7](https://tecyfy.com/prices/compare/grok-4-5-vs-grok-4-7.md)
- [Grok 4.3 vs Grok 4.7](https://tecyfy.com/prices/compare/grok-4-3-vs-grok-4-7.md)
- [Grok 4.20 (non-reasoning) vs Grok 4.7](https://tecyfy.com/prices/compare/grok-4-20-0309-non-reasoning-vs-grok-4-7.md)
- [Grok 4.7 vs Grok Build 0.1](https://tecyfy.com/prices/compare/grok-4-7-vs-grok-build-0-1.md)
- [Grok 4.20 Multi-agent vs Grok 4.7](https://tecyfy.com/prices/compare/grok-4-20-multi-agent-0309-vs-grok-4-7.md)