GLM-4.5-Air vs Apertus 8B vs Seed 1.6 Vision
Seed 1.6 Vision comes out ahead, 63 to 56 and 49 on our weighted score, though Apertus 8B is 3.1× cheaper per token.
Z.ai (Zhipu)GLM-4.5-Air
49/100- ECI—
- Price$0.20 / $1.10
- Context131K
Swiss AI
Apertus 8B
56/100- ECI—
- Price$0.10 / $0.20
- Context66K
- Our pick
ByteDance SeedSeed 1.6 Vision
63/100- ECI—
- Price$0.119 / $1.19
- Context256K
Seed 1.6 Vision is our pick
Seed 1.6 Vision is the better all-round choice, scoring 63/100 against Apertus 8B (56) and GLM-4.5-Air (49). It leads on inputs & features and context window. Apertus 8B wins on price. 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 priceApertus 8BApertus 8B $0.125 · 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 · Apertus 8B 65,536 tokens
- Widest inputsSeed 1.6 VisionGLM-4.5-Air: Text · Apertus 8B: Text · Seed 1.6 Vision: Text, Images
- Self-hostingGLM-4.5-Air and Apertus 8BPublishes downloadable weights (Apache-2.0)
| Measure | Weight | GLM-4.5-Air | Apertus 8B | Seed 1.6 Vision |
|---|---|---|---|---|
| Price | 50% | 68 | 93 | 69 |
| Inputs & features | 30% | 35 | 25 | 70 |
| Context window | 20% | 24 | 12 | 36 |
| Overall | 100% | 49/100 | 56/100 | 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) | Apertus 8BSwiss AI | Seed 1.6 VisionByteDance Seed |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | — | — | — |
| ECI rank | — | — | — |
| Price per million tokens | |||
| Input | $0.20 | $0.10 (best) | $0.119 |
| Output | $1.10 | $0.20 (best) | $1.19 |
| Cached input | $0.03 | — | $0.024 (best) |
| Blended (3:1) | $0.425 | $0.125 (best) | $0.386 |
| Long-context rate | Same rate | Same rate | Over 32K: $0.178 / $2.37 |
| Price source | Official Z.AI API | Median of 1 providers | Official Volcengine Ark API |
| Limits | |||
| Context window | 131,072 tokens | 65,536 tokens | 256,000 tokens (best) |
| Max output | 98,304 tokens (best) | 8,192 tokens | 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 | No | Yes |
| Tool calling | Yes | Yes | Yes |
| Structured output | No | No | Yes |
| Availability | |||
| Weights | Open | OpenApache-2.0 | Proprietary |
| API model ID | glm-4.5-air | — | doubao-seed-1-6-vision-250815 |
| API providers | 13 (best) | 1 | 2 |
| Released | Jul 28, 2025 | Sep 2, 2025 | Aug 15, 2025 |
| Knowledge cutoff | Apr 2025 | Sep 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
- Apertus 8B$1.40
- Seed 1.6 Vision$3.56
Which should you choose?
Which is better: GLM-4.5-Air, Apertus 8B or Seed 1.6 Vision?
Seed 1.6 Vision is the better all-round choice, scoring 63/100 against Apertus 8B (56) and GLM-4.5-Air (49). It leads on inputs & features and context window. Apertus 8B wins on price. 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, Apertus 8B or Seed 1.6 Vision?
Apertus 8B is cheaper at $0.10 input / $0.20 output per million tokens (median across 1 API provider). 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). At a typical mix of three input tokens to one output token, that is $0.125 per million tokens for Apertus 8B versus $0.386 for Seed 1.6 Vision (3.1× as much) and $0.425 for GLM-4.5-Air (3.4× as much).
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, Apertus 8B 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, Apertus 8B 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 65,536 for Apertus 8B. Maximum output per response: GLM-4.5-Air up to 98,304, Apertus 8B up to 8,192, Seed 1.6 Vision up to 32,000 tokens.
Which can read images, PDFs, audio or video?
GLM-4.5-Air accepts text; Apertus 8B 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 and Apertus 8B publishes its weights (Apache-2.0) and can be self-hosted; Seed 1.6 Vision is proprietary.
Which is newer?
Apertus 8B is the newest, released Sep 2, 2025. Seed 1.6 Vision came out Aug 15, 2025; GLM-4.5-Air came out Jul 28, 2025. Knowledge cutoff: GLM-4.5-Air Apr 2025, Apertus 8B Sep 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.
