ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Apertus 8B vs GLM-4.5-Air 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.

  1. Swiss AI

    Apertus 8B

    Released Sep 2, 2025

    56/100
    • ECI—
    • Price$0.10 / $0.20
    • Context66K
  2. Z.ai (Zhipu)

    GLM-4.5-Air

    Released Jul 28, 2025

    49/100
    • ECI—
    • Price$0.20 / $1.10
    • Context131K
  3. Our pick

    ByteDance Seed

    Seed 1.6 Vision

    Released Aug 15, 2025

    63/100
    • ECI—
    • Price$0.119 / $1.19
    • Context256K
01 — Verdict

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 VisionApertus 8B: Text · GLM-4.5-Air: Text · Seed 1.6 Vision: Text, Images
  • Self-hostingApertus 8B and GLM-4.5-AirPublishes downloadable weights (Apache-2.0)
How the score is built
MeasureWeightApertus 8BGLM-4.5-AirSeed 1.6 Vision
Price50%936869
Inputs & features30%253570
Context window20%122436
Overall100%56/10049/10063/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Apertus 8B vs GLM-4.5-Air vs Seed 1.6 Vision specifications side by side
SpecificationApertus 8BSwiss AIGLM-4.5-AirZ.ai (Zhipu)Seed 1.6 VisionByteDance Seed
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.10 (best)$0.20$0.119
Output$0.20 (best)$1.10$1.19
Cached input—$0.03$0.024 (best)
Blended (3:1)$0.125 (best)$0.425$0.386
Long-context rateSame rateSame rateOver 32K: $0.178 / $2.37
Price sourceMedian of 1 providersOfficial Z.AI APIOfficial Volcengine Ark API
Limits
Context window65,536 tokens131,072 tokens256,000 tokens (best)
Max output8,192 tokens98,304 tokens (best)32,000 tokens
Inputs and features
TextYesYesYes
ImagesNoNoYes
PDFsNoNoNo
AudioNoNoNo
VideoNoNoNo
ReasoningNoYesYes
Tool callingYesYesYes
Structured outputNoNoYes
Availability
WeightsOpenApache-2.0OpenProprietary
API model ID—glm-4.5-airdoubao-seed-1-6-vision-250815
API providers113 (best)2
ReleasedSep 2, 2025Jul 28, 2025Aug 15, 2025
Knowledge cutoffSep 2025Apr 2025—
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Apertus 8B$1.40
  • GLM-4.5-Air$4.20
  • Seed 1.6 Vision$3.56
04 — Questions

Which should you choose?

Which is better: Apertus 8B, GLM-4.5-Air 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, Apertus 8B, GLM-4.5-Air 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. Apertus 8B has not been scored yet, GLM-4.5-Air 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 Apertus 8B, GLM-4.5-Air 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: Apertus 8B up to 8,192, GLM-4.5-Air up to 98,304, Seed 1.6 Vision up to 32,000 tokens.

Which can read images, PDFs, audio or video?

Apertus 8B accepts text; GLM-4.5-Air 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?

Apertus 8B and GLM-4.5-Air 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: Apertus 8B Sep 2025, GLM-4.5-Air 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.