# DeepSeek V4.1 Flash vs Qwen3.8-Flash

Qwen3.8-Flash is the cheaper of the 2: for the same tokens, 3 read for each 1 written, DeepSeek V4.1 Flash costs 2.3 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/deepseek-flash-vs-qwen3-8-flash
- Makers: DeepSeek V4.1 Flash from DeepSeek, Qwen3.8-Flash from Alibaba

## Price per million tokens, in US dollars

| | DeepSeek V4.1 Flash | Qwen3.8-Flash |
| --- | --: | --: |
| Input | $0.30 | $0.15 |
| Cached input | $0.006 | $0.016 |
| Cache write | not listed | not listed |
| Output | $1.20 | $0.47 |
| Blend, 3 read for each 1 written | $0.525 | $0.23 |
| Batch input | not listed | not listed |
| Batch output | not listed | not listed |
| Context window, tokens | 1M | not listed |
| Capability score (Epoch Capabilities Index; GPT-5 is 150) | 156 | not listed |
| Longest answer, tokens | not listed | not listed |

DeepSeek V4.1 Flash: The peak-hours price. Off-peak hours are half. Peak is 01:00 to 04:00 and 06:00 to 10:00 UTC on weekdays.

## 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:

- DeepSeek V4.1 Flash: 2,063 tokens. Counted with the tokenizer DeepSeek publishes with V4-Pro and V4.1 Flash, the same models its API serves.
- Qwen3.8-Flash: about 2,100 tokens. Counted with the tokenizer Alibaba publishes with its open Qwen3.8 models. Alibaba does not say its API models use the same one, so the count is marked as about.

## 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 | DeepSeek V4.1 Flash | Qwen3.8-Flash |
| --- | --- | --: | --: |
| A chat question | 300, 500, 100 | $2.07 | 84 cents |
| A hard question, with thinking | 300, 1,400, 100 | $5.31 | $2.11 |
| A long report, summarised | 60,000, 2,000, 20 | $12.24 | $5.96 |
| A 40-turn agent task | 2,800,000, 40,000, 10 | $44.14 | $30.34 |
| A support bot's reply | 4,000, 300, 2,000 | $58.32 | $28.38 |
| Sort a message into a category | 250, 5, 50,000 | $122 | $59.77 |
| Read an invoice into fields | 1,500, 250, 1,000 | $22.50 | $10.27 |
| Review a pull request | 25,000, 4,500, 50 | $19.35 | $8.80 |

## Questions

### Which is cheaper, DeepSeek V4.1 Flash or Qwen3.8-Flash?

Qwen3.8-Flash is cheaper: $0.15 per million tokens read and $0.47 per million written, against $0.30 and $1.20 on DeepSeek V4.1 Flash. On a mix of 3 tokens read for each 1 written, DeepSeek V4.1 Flash costs 2.3 times as much.

### Which is better, DeepSeek V4.1 Flash or Qwen3.8-Flash?

DeepSeek V4.1 Flash scores 156 on the Epoch Capabilities Index, an independent score from Epoch AI that combines over 50 benchmarks (GPT-5 is 150). Qwen3.8-Flash 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 DeepSeek V4.1 Flash and Qwen3.8-Flash?

At 2,000 replies a day, each reading 4,000 tokens (50 percent of them from cache) and writing 300, it costs $58.32 a month on DeepSeek V4.1 Flash and $28.38 on Qwen3.8-Flash: DeepSeek V4.1 Flash costs 2.1 times as much for this job.

### What does an AI agent task cost on DeepSeek V4.1 Flash and Qwen3.8-Flash?

One 40-turn task that reads 2,800,000 tokens in all, 90 percent of them from cache, and writes 40,000, costs 15 cents on DeepSeek V4.1 Flash and 10 cents on Qwen3.8-Flash. At 10 tasks a day that is $44.14 and $30.34 a month.

### Does the same text take the same number of tokens on DeepSeek V4.1 Flash and Qwen3.8-Flash?

No. Our lesson "How AI writes", 1,700 words long, is 2,063 tokens on DeepSeek V4.1 Flash and about 2,100 on Qwen3.8-Flash. Each maker cuts text its own way, and every extra token is paid for at the model's price.

### Can I pay less on DeepSeek V4.1 Flash and Qwen3.8-Flash 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

- [DeepSeek: API prices](https://api-docs.deepseek.com/quick_start/pricing)
- [Alibaba: API prices](https://www.qwencloud.com/pricing/api)
- [Epoch Capabilities Index, by Epoch AI (CC BY 4.0)](https://epoch.ai/benchmarks/eci)

## Other comparisons

- [Qwen3.7-Max vs Qwen3.8-Flash](https://tecyfy.com/prices/compare/qwen3-7-max-vs-qwen3-8-flash.md)
- [Qwen3.7-Plus vs Qwen3.8-Flash](https://tecyfy.com/prices/compare/qwen3-7-plus-vs-qwen3-8-flash.md)
- [Qwen3.7-Flash vs Qwen3.8-Flash](https://tecyfy.com/prices/compare/qwen3-7-flash-vs-qwen3-8-flash.md)
- [DeepSeek V4.1 Flash vs GPT-6 Luna](https://tecyfy.com/prices/compare/deepseek-flash-vs-gpt-6-luna.md)
- [GPT-6 Luna vs Qwen3.8-Flash](https://tecyfy.com/prices/compare/gpt-6-luna-vs-qwen3-8-flash.md)
- [Claude Haiku 5.5 vs DeepSeek V4.1 Flash](https://tecyfy.com/prices/compare/claude-haiku-5-5-vs-deepseek-flash.md)