GLM-4.5-Air vs GLM-4.5-Flash vs Seed 1.6 Vision
Too close to call on our weighted score (GLM-4.5-Flash 65, Seed 1.6 Vision 63, GLM-4.5-Air 49). The right pick depends on what you value most.
Z.ai (Zhipu)GLM-4.5-Air
49/100- ECI—
- Price$0.20 / $1.10
- Context131K
- Z.ai (Zhipu)
GLM-4.5-Flash
65/100- ECI—
- PriceFree / Free
- Context131K
ByteDance SeedSeed 1.6 Vision
63/100- ECI—
- Price$0.119 / $1.19
- Context256K
Too close to call
It is close. Our weighted score puts them within 2 points (GLM-4.5-Flash 65/100, Seed 1.6 Vision 63/100, GLM-4.5-Air 49/100), so choose by what matters most for your work: GLM-4.5-Flash on price and Seed 1.6 Vision for long inputs. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
- CapabilityNot enough dataNo independent benchmark covers every model here yet
- Lowest priceGLM-4.5-FlashGLM-4.5-Flash Free · Seed 1.6 Vision $0.386 · GLM-4.5-Air $0.425 per 1M tokens (3:1 blend)
- Longest contextSeed 1.6 VisionSeed 1.6 Vision 256,000 · GLM-4.5-Air 131,072 · GLM-4.5-Flash 131,072 tokens
- Widest inputsSeed 1.6 VisionGLM-4.5-Air: Text · GLM-4.5-Flash: Text · Seed 1.6 Vision: Text, Images
- Self-hostingGLM-4.5-AirPublishes downloadable weights
| Measure | Weight | GLM-4.5-Air | GLM-4.5-Flash | Seed 1.6 Vision |
|---|---|---|---|---|
| Price | 50% | 68 | 100 | 69 |
| Inputs & features | 30% | 35 | 35 | 70 |
| Context window | 20% | 24 | 24 | 36 |
| Overall | 100% | 49/100 | 65/100 | 63/100 |
Left out because at least one model lacks the data: capability. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | GLM-4.5-AirZ.ai (Zhipu) | GLM-4.5-FlashZ.ai (Zhipu) | Seed 1.6 VisionByteDance Seed |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | — | — | — |
| ECI rank | — | — | — |
| Price per million tokens | |||
| Input | $0.20 | Free (best) | $0.119 |
| Output | $1.10 | Free (best) | $1.19 |
| Cached input | $0.03 | — | $0.024 (best) |
| Blended (3:1) | $0.425 | Free (best) | $0.386 |
| Long-context rate | Same rate | Same rate | Over 32K: $0.178 / $2.37 |
| Price source | Official Z.AI API | Official Z.AI API | Official Volcengine Ark API |
| Limits | |||
| Context window | 131,072 tokens | 131,072 tokens | 256,000 tokens (best) |
| Max output | 98,304 tokens (best) | 98,304 tokens (best) | 32,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | No | No | Yes |
| PDFs | No | No | No |
| Audio | No | No | No |
| Video | No | No | No |
| Reasoning | Yes | Yes | Yes |
| Tool calling | Yes | Yes | Yes |
| Structured output | No | No | Yes |
| Availability | |||
| Weights | Open | Proprietary | Proprietary |
| API model ID | glm-4.5-air | glm-4.5-flash | doubao-seed-1-6-vision-250815 |
| API providers | 13 (best) | 4 | 2 |
| Released | Jul 28, 2025 | Jul 28, 2025 | Aug 15, 2025 |
| Knowledge cutoff | Apr 2025 | Apr 2025 | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- GLM-4.5-Air$4.20
- GLM-4.5-FlashFree
- Seed 1.6 Vision$3.56
Which should you choose?
Which is better: GLM-4.5-Air, GLM-4.5-Flash or Seed 1.6 Vision?
It is close. Our weighted score puts them within 2 points (GLM-4.5-Flash 65/100, Seed 1.6 Vision 63/100, GLM-4.5-Air 49/100), so choose by what matters most for your work: GLM-4.5-Flash on price and Seed 1.6 Vision for long inputs. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
Which is cheaper, GLM-4.5-Air, GLM-4.5-Flash or Seed 1.6 Vision?
GLM-4.5-Flash is cheaper at Free input / Free output per million tokens (official Z.AI API price). Seed 1.6 Vision costs $0.119 input / $1.19 output per million tokens (official Volcengine Ark API price); GLM-4.5-Air costs $0.20 input / $1.10 output per million tokens (official Z.AI API price). GLM-4.5-Flash is listed as free.
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. GLM-4.5-Air has not been scored yet, GLM-4.5-Flash has not been scored yet and Seed 1.6 Vision has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for GLM-4.5-Air, GLM-4.5-Flash and Seed 1.6 Vision yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. All three support tool calling for agent workflows.
Which has the bigger context window?
Seed 1.6 Vision has the largest context window at 256,000 tokens, against 131,072 for GLM-4.5-Air and 131,072 for GLM-4.5-Flash. Maximum output per response: GLM-4.5-Air up to 98,304, GLM-4.5-Flash up to 98,304, Seed 1.6 Vision up to 32,000 tokens.
Which can read images, PDFs, audio or video?
GLM-4.5-Air accepts text; GLM-4.5-Flash accepts text; Seed 1.6 Vision accepts text and images. Seed 1.6 Vision handles the widest range of inputs.
Are any of these open source?
GLM-4.5-Air publishes its weights and can be self-hosted; GLM-4.5-Flash and Seed 1.6 Vision is proprietary.
Which is newer?
Seed 1.6 Vision is the newest, released Aug 15, 2025. GLM-4.5-Air came out Jul 28, 2025; GLM-4.5-Flash came out Jul 28, 2025. Knowledge cutoff: GLM-4.5-Air Apr 2025, GLM-4.5-Flash Apr 2025.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
