// head_to_head
DeepSeek V4.1 Flash vs GLM 5.1
Published LiveBench scores across all seven categories, live list pricing, context windows, and the measured cost of a point of capability — for both models, side by side.
DeepSeek V4.1 Flash is the cheaper of the two; neither can be ranked on quality here.
GLM 5.1 does not have a published LiveBench run, so this comparison covers price, context and declared capabilities only. A missing score means "not evaluated", not "worse" — the right way to separate these two is an eval on your own workload.
deepseek
DeepSeek V4.1 Flash
- Blended / 1M
- $0.200
- Context
- 1.0M
- Released
- Sep 10, 2026
- Overall score
- 81.1
z-ai
GLM 5.1
- Blended / 1M
- $1.48
- Context
- 205K
- Released
- Apr 7, 2026
- Overall score
- Not evaluated
Specs and pricing
| Metric | DeepSeek V4.1 Flash | GLM 5.1 |
|---|---|---|
| LiveBench overall Mean of the seven LiveBench category scores, 0–100. Higher is better. | 81.1 | — |
| Cost per point Measured benchmark spend divided by overall score — dollars per point of capability. | $0.0157 | — |
| Blended price / 1M 3:1 input:output mix, the usual shape of production traffic. | $0.200win | $1.48 |
| Input price / 1M | $0.100win | $0.966 |
| Output price / 1M | $0.500win | $3.04 |
| Cached input / 1M Price of an input token served from the prompt cache, where the provider publishes one. | $0.010win | $0.179 |
| Context window | 1.0Mwin | 205K |
| Max output tokens | 944Kwin | 128K |
Benchmarks by category
An overall score averages away the thing you probably care about. These are the seven LiveBench categories scored separately — DeepSeek V4.1 Flash on top, GLM 5.1 below, both out of 100.
What each one costs to run
Per-token prices are hard to feel. These are monthly list costs for both models across five workload shapes, using each provider's published cached-input rate where there is one.
| Workload | DeepSeek V4.1 Flash | GLM 5.1 |
|---|---|---|
| Support chatbot 1.2K in / 400 out × 200K requests | $57.52/mo | $418.08/mo |
| RAG assistant 8K in / 600 out × 100K requests | $74.00/mo | $640.32/mo |
| Coding agent 40K in / 4K out × 20K requests | $69.60/mo | $575.18/mo |
| Document extraction 20K in / 1.5K out × 50K requests | $133.00/mo | $1,154/mo |
| Bulk classification 500 in / 20 out × 5M requests | $255.00/mo | $2,325/mo |
Which should you pick?
You need to fit large documents in one call
DeepSeek V4.1 Flash
Wider context window — 1.0M against 205K.
DeepSeek V4.1 Flash vs GLM 5.1 FAQ
Which is better, DeepSeek V4.1 Flash or GLM 5.1?
DeepSeek V4.1 Flash is the cheaper of the two; neither can be ranked on quality here. GLM 5.1 does not have a published LiveBench run, so this comparison covers price, context and declared capabilities only. A missing score means "not evaluated", not "worse" — the right way to separate these two is an eval on your own workload.
Is DeepSeek V4.1 Flash cheaper than GLM 5.1?
DeepSeek V4.1 Flash is cheaper. On a 3:1 input:output blend, DeepSeek V4.1 Flash lists at $0.200 per million tokens and GLM 5.1 at $1.48 — DeepSeek V4.1 Flash is 7.4× cheaper. Input and output are priced separately — DeepSeek V4.1 Flash charges $0.100 in and $0.500 out, GLM 5.1 charges $0.966 and $3.04 — so the model that looks cheaper flips depending on how output-heavy your workload is.
Does DeepSeek V4.1 Flash or GLM 5.1 have a bigger context window?
DeepSeek V4.1 Flash has the larger context window: 1.0M for DeepSeek V4.1 Flash against 205K for GLM 5.1. Note that a window you can fill is not a window you should fill — retrieval quality usually degrades well before the limit, and you pay for every token you put in it.
Do DeepSeek V4.1 Flash and GLM 5.1 support prompt caching?
Both publish a cached-input rate: $0.010 per million for DeepSeek V4.1 Flash and $0.179 for GLM 5.1, against full input rates of $0.100 and $0.966. On a workload with a long stable prefix — a system prompt, a tool schema, a retrieved corpus — that changes the economics more than the headline price does.
Related comparisons
How these numbers are produced
- Price — provider list price from OpenRouter, refreshed every 15 minutes. “Blended” is a 3:1 input:output mix.
- Scores — LiveBench release 2026-06-25, using their own category map. Each model shows its strongest published run. A blank means “not evaluated”, never “bad”.
- Cost per point — the measured dollars LiveBench spent on the run, divided by the score it earned.
- “Win” — awarded only past a threshold: one full point on a benchmark score, 10% on a price, 25% on a context window. Anything tighter reports as a tie, because effort settings alone move a LiveBench score by more than that.
Published benchmarks rank models on someone else's tasks. Before committing, see LLM & agent evaluation for building an eval on your own.