ZMIME
Comparison · 2 models · Updated Oct 4, 2026

GLM-5.3 vs Solar Pro 4

Solar Pro 4 comes out ahead, 55 to 43 on our weighted score, and it is the cheaper option too.

  1. Z.ai (Zhipu)

    GLM-5.3

    Released Aug 14, 2026

    43/100
    • ECI155.8
    • Price$1.40 / $4.40
    • Context1M
  2. Our pick

    Upstage

    Solar Pro 4

    Released Aug 6, 2026

    55/100
    • ECI—
    • Price$0.30 / $1.20
    • Context524K
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Solar Pro 4 is our pick

Solar Pro 4 is the better all-round choice, scoring 55/100 against GLM-5.3 (43). It leads on price. GLM-5.3 wins on context window. 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 priceSolar Pro 4Solar Pro 4 $0.525 · GLM-5.3 $2.15 per 1M tokens (3:1 blend)
  • Longest contextGLM-5.3GLM-5.3 1,000,000 · Solar Pro 4 524,288 tokens
  • Widest inputsSame inputsGLM-5.3: Text · Solar Pro 4: Text
  • Self-hostingGLM-5.3Publishes downloadable weights
How the score is built
MeasureWeightGLM-5.3Solar Pro 4
Price50%3463
Inputs & features30%4545
Context window20%6049
Overall100%43/10055/100

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-5.3 vs Solar Pro 4 specifications side by side
SpecificationGLM-5.3Z.ai (Zhipu)Solar Pro 4Upstage
Capability
Capabilities Index (ECI)155.8—
ECI rank#24 of 148—
GPQA DiamondGraduate-level science questions90.9%—
FrontierMath Tiers 1–3Research-level mathematics68.8%—
OTIS Mock AIME 2024–2025Competition mathematics91.1%—
SimpleQA VerifiedShort factual questions41.0%—
Price per million tokens
Input$1.40$0.30 (best)
Output$4.40$1.20 (best)
Cached input$0.26$0.06 (best)
Blended (3:1)$2.15$0.525 (best)
Long-context rateSame rateSame rate
Price sourceOfficial Z.AI APIOfficial Upstage API
Limits
Context window1,000,000 tokens (best)524,288 tokens
Max output131,072 tokens131,072 tokens
Inputs and features
TextYesYes
ImagesNoNo
PDFsNoNo
AudioNoNo
VideoNoNo
ReasoningYeslow · high · maxYesminimal · low · medium · high · xhigh · max
Tool callingYesYes
Structured outputYesYes
Availability
WeightsOpenProprietary
API model IDglm-5.3solar-pro4
API providers62 (best)3
ReleasedAug 14, 2026Aug 6, 2026
Knowledge cutoff—Feb 2026
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-5.3$22.80
  • Solar Pro 4$5.40
04 — Questions

Which should you choose?

Which is better: GLM-5.3 or Solar Pro 4?

Solar Pro 4 is the better all-round choice, scoring 55/100 against GLM-5.3 (43). It leads on price. GLM-5.3 wins on context window. 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-5.3 or Solar Pro 4?

Solar Pro 4 is cheaper at $0.30 input / $1.20 output per million tokens (official Upstage API price). GLM-5.3 costs $1.40 input / $4.40 output per million tokens (official Z.AI API price). At a typical mix of three input tokens to one output token, that is $0.525 per million tokens for Solar Pro 4 versus $2.15 for GLM-5.3 (4.1× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. GLM-5.3 has an ECI of 155.8 and Solar Pro 4 has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for GLM-5.3 and Solar Pro 4 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

GLM-5.3 has the largest context window at 1,000,000 tokens, against 524,288 for Solar Pro 4. Maximum output per response: GLM-5.3 up to 131,072, Solar Pro 4 up to 131,072 tokens.

Which can read images, PDFs, audio or video?

GLM-5.3 accepts text; Solar Pro 4 accepts text. They handle the same number of input types.

Are any of these open source?

GLM-5.3 publishes its weights and can be self-hosted; Solar Pro 4 is proprietary.

Which is newer?

GLM-5.3 is the newest, released Aug 14, 2026. Solar Pro 4 came out Aug 6, 2026. Knowledge cutoff: Solar Pro 4 Feb 2026.

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.