# Gemini 3.8 Flash vs Grok 4.7

Gemini 3.8 Flash is the cheaper of the 2: for the same tokens, 3 read for each 1 written, Grok 4.7 costs 2 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/gemini-3-8-flash-vs-grok-4-7
- Makers: Gemini 3.8 Flash from Google, Grok 4.7 from xAI

## Price per million tokens, in US dollars

| | Gemini 3.8 Flash | Grok 4.7 |
| --- | --: | --: |
| Input | $0.75 | $2 |
| Cached input | $0.075 | $0.50 |
| Cache write | not listed | not listed |
| Output | $3.75 | $6 |
| Blend, 3 read for each 1 written | $1.50 | $3 |
| Batch input | not listed | not listed |
| Batch output | not listed | not listed |
| Long prompt input (above 200K on Grok 4.7) | $0.75 | $4 |
| Long prompt output | $3.75 | $12 |
| Context window, tokens | 1.05M | 500K |
| Capability score (Epoch Capabilities Index; GPT-5 is 150) | 157 | 154 |
| Longest answer, tokens | 66K | not listed |

Gemini 3.8 Flash: Until 31 December 2026. From 1 January 2027 it is $1.50 in, $7.50 out and $0.15 cached.

## The same text, counted by each maker

Our lesson "How AI writes" (https://tecyfy.com/learn/how-ai-works/how-ai-writes), about 1,700 words of English:

- Gemini 3.8 Flash: about 2,200 tokens. Google does not publish the Gemini tokenizer. Its rule is that a token is about 4 characters, so the count is the characters divided by 4.
- Grok 4.7: about 2,100 tokens. xAI publishes neither its tokenizer nor a rule for estimating. The figure is OpenAI's o200k_base count, a rough guide only.

## 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 | Gemini 3.8 Flash | Grok 4.7 |
| --- | --- | --: | --: |
| A chat question | 300, 500, 100 | $6.30 | $10.80 |
| A hard question, with thinking | 300, 1,400, 100 | $16.43 | $27.00 |
| A long report, summarised | 60,000, 2,000, 20 | $31.50 | $79.20 |
| A 40-turn agent task | 2,800,000, 40,000, 10 | $165 | $618 |
| A support bot's reply | 4,000, 300, 2,000 | $166 | $408 |
| Sort a message into a category | 250, 5, 50,000 | $309 | $795 |
| Read an invoice into fields | 1,500, 250, 1,000 | $61.88 | $135 |
| Review a pull request | 25,000, 4,500, 50 | $53.44 | $116 |

## Questions

### Which is cheaper, Gemini 3.8 Flash or Grok 4.7?

Gemini 3.8 Flash is cheaper: $0.75 per million tokens read and $3.75 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 2 times as much.

### Which is better, Gemini 3.8 Flash or Grok 4.7?

On the Epoch Capabilities Index, an independent score from Epoch AI that combines over 50 benchmarks, Gemini 3.8 Flash scores 157 and Grok 4.7 154, above the top of the range of doubt around Grok 4.7's score (GPT-5 is 150). One score is an average; test both on your own work before you switch.

### What does a support bot cost a month on Gemini 3.8 Flash 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 $166 a month on Gemini 3.8 Flash and $408 on Grok 4.7: Grok 4.7 costs 2.5 times as much for this job.

### What does an AI agent task cost on Gemini 3.8 Flash 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 55 cents on Gemini 3.8 Flash and $2.06 on Grok 4.7. At 10 tasks a day that is $165 and $618 a month.

### Which has the larger context window, Gemini 3.8 Flash or Grok 4.7?

Gemini 3.8 Flash, with 1.05M 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 Gemini 3.8 Flash and Grok 4.7?

No. Our lesson "How AI writes", 1,700 words long, is about 2,200 tokens on Gemini 3.8 Flash and about 2,100 on Grok 4.7. Each maker cuts text its own way, and every extra token is paid for at the model's price.

### Can I pay less on Gemini 3.8 Flash 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

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

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