ZMIME
Comparison · 3 models · Updated Oct 4, 2026

GLM-4.5-Air vs Seed 1.6 vs Seed 1.6 Vision

Seed 1.6 Vision comes out ahead, 63 to 55 and 49 on our weighted score.

  1. Z.ai (Zhipu)

    GLM-4.5-Air

    Released Jul 28, 2025

    49/100
    • ECI—
    • Price$0.20 / $1.10
    • Context131K
  2. ByteDance Seed

    Seed 1.6

    Released Oct 15, 2025

    55/100
    • ECI—
    • Price$0.119 / $1.19
    • Context256K
  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 Seed 1.6 (55) and GLM-4.5-Air (49). It leads on inputs & features. 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 priceSeed 1.6 and Seed 1.6 VisionSeed 1.6 $0.386 · Seed 1.6 Vision $0.386 · GLM-4.5-Air $0.425 per 1M tokens (3:1 blend)
  • Longest contextSeed 1.6 and Seed 1.6 VisionSeed 1.6 256,000 · Seed 1.6 Vision 256,000 · GLM-4.5-Air 131,072 tokens
  • Widest inputsSeed 1.6 VisionGLM-4.5-Air: Text · Seed 1.6: Text · Seed 1.6 Vision: Text, Images
  • Self-hostingGLM-4.5-AirPublishes downloadable weights
How the score is built
MeasureWeightGLM-4.5-AirSeed 1.6Seed 1.6 Vision
Price50%686969
Inputs & features30%354570
Context window20%243636
Overall100%49/10055/10063/100

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.

GLM-4.5-Air vs Seed 1.6 vs Seed 1.6 Vision specifications side by side
SpecificationGLM-4.5-AirZ.ai (Zhipu)Seed 1.6ByteDance SeedSeed 1.6 VisionByteDance Seed
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.20$0.119 (best)$0.119 (best)
Output$1.10 (best)$1.19$1.19
Cached input$0.03$0.024 (best)$0.024 (best)
Blended (3:1)$0.425$0.386 (best)$0.386 (best)
Long-context rateSame rateOver 32K: $0.178 / $2.37Over 32K: $0.178 / $2.37
Price sourceOfficial Z.AI APIOfficial Volcengine Ark APIOfficial Volcengine Ark API
Limits
Context window131,072 tokens256,000 tokens (best)256,000 tokens (best)
Max output98,304 tokens (best)64,000 tokens32,000 tokens
Inputs and features
TextYesYesYes
ImagesNoNoYes
PDFsNoNoNo
AudioNoNoNo
VideoNoNoNo
ReasoningYesYesminimal · low · medium · highYes
Tool callingYesYesYes
Structured outputNoYesYes
Availability
WeightsOpenProprietaryProprietary
API model IDglm-4.5-airdoubao-seed-1-6-251015doubao-seed-1-6-vision-250815
API providers13 (best)22
ReleasedJul 28, 2025Oct 15, 2025Aug 15, 2025
Knowledge cutoffApr 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.

  • GLM-4.5-Air$4.20
  • Seed 1.6$3.56
  • Seed 1.6 Vision$3.56
04 — Questions

Which should you choose?

Which is better: GLM-4.5-Air, Seed 1.6 or Seed 1.6 Vision?

Seed 1.6 Vision is the better all-round choice, scoring 63/100 against Seed 1.6 (55) and GLM-4.5-Air (49). It leads on inputs & features. 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, Seed 1.6 or Seed 1.6 Vision?

Seed 1.6 is cheaper at $0.119 input / $1.19 output per million tokens (official Volcengine Ark 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). At a typical mix of three input tokens to one output token, that is $0.386 per million tokens for Seed 1.6 versus $0.386 for Seed 1.6 Vision (1× as much) and $0.425 for GLM-4.5-Air (1.1× 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, Seed 1.6 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, Seed 1.6 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 and Seed 1.6 Vision have the largest context windows (256,000 and 256,000 tokens), against 131,072 for GLM-4.5-Air. Maximum output per response: GLM-4.5-Air up to 98,304, Seed 1.6 up to 64,000, Seed 1.6 Vision up to 32,000 tokens.

Which can read images, PDFs, audio or video?

GLM-4.5-Air accepts text; Seed 1.6 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; Seed 1.6 and Seed 1.6 Vision is proprietary.

Which is newer?

Seed 1.6 is the newest, released Oct 15, 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.

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.