GLM-5.3 vs Muse Spark 1.2 vs Solar Pro 4
Muse Spark 1.2 comes out ahead, 60 to 55 and 43 on our weighted score, though Solar Pro 4 is 3.8× cheaper per token.
Z.ai (Zhipu)GLM-5.3
43/100- ECI155.8
- Price$1.40 / $4.40
- Context1M
- Our pick
MetaMuse Spark 1.2
60/100- ECI155.0
- Price$1.25 / $4.25
- Context1.05M
Upstage
Solar Pro 4
55/100- ECI—
- Price$0.30 / $1.20
- Context524K
Muse Spark 1.2 is our pick
Muse Spark 1.2 is the better all-round choice, scoring 60/100 against Solar Pro 4 (55) and GLM-5.3 (43). It leads on inputs & features. Solar Pro 4 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 priceSolar Pro 4Solar Pro 4 $0.525 · Muse Spark 1.2 $2.00 · GLM-5.3 $2.15 per 1M tokens (3:1 blend)
- Longest contextMuse Spark 1.2Muse Spark 1.2 1,048,576 · GLM-5.3 1,000,000 · Solar Pro 4 524,288 tokens
- Widest inputsMuse Spark 1.2GLM-5.3: Text · Muse Spark 1.2: Text, Images, PDFs, Audio, Video · Solar Pro 4: Text
- Self-hostingGLM-5.3Publishes downloadable weights
| Measure | Weight | GLM-5.3 | Muse Spark 1.2 | Solar Pro 4 |
|---|---|---|---|---|
| Price | 50% | 34 | 36 | 63 |
| Inputs & features | 30% | 45 | 100 | 45 |
| Context window | 20% | 60 | 61 | 49 |
| Overall | 100% | 43/100 | 60/100 | 55/100 |
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-5.3Z.ai (Zhipu) | Muse Spark 1.2Meta | Solar Pro 4Upstage |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 155.8 (best) | 155.0 | — |
| ECI rank | #24 of 148 (best) | #30 of 148 | — |
| GPQA DiamondGraduate-level science questions | 90.9% | — | — |
| FrontierMath Tiers 1–3Research-level mathematics | 68.8% | — | — |
| OTIS Mock AIME 2024–2025Competition mathematics | 91.1% | — | — |
| SimpleQA VerifiedShort factual questions | 41.0% | 60.3% (best) | — |
| Price per million tokens | |||
| Input | $1.40 | $1.25 | $0.30 (best) |
| Output | $4.40 | $4.25 | $1.20 (best) |
| Cached input | $0.26 | $0.15 | $0.06 (best) |
| Blended (3:1) | $2.15 | $2.00 | $0.525 (best) |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official Z.AI API | Official Meta API | Official Upstage API |
| Limits | |||
| Context window | 1,000,000 tokens | 1,048,576 tokens (best) | 524,288 tokens |
| Max output | 131,072 tokens | 131,072 tokens | 131,072 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | No | Yes | No |
| PDFs | No | Yes | No |
| Audio | No | Yes | No |
| Video | No | Yes | No |
| Reasoning | Yeslow · high · max | Yesminimal · low · medium · high · xhigh | Yesminimal · low · medium · high · xhigh · max |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | Yes |
| Availability | |||
| Weights | Open | Proprietary | Proprietary |
| API model ID | glm-5.3 | muse-spark-1.2 | solar-pro4 |
| API providers | 62 (best) | 15 | 3 |
| Released | Aug 14, 2026 | Aug 5, 2026 | Aug 6, 2026 |
| Knowledge cutoff | — | — | Feb 2026 |
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
- Muse Spark 1.2$21.00
- Solar Pro 4$5.40
Which should you choose?
Which is better: GLM-5.3, Muse Spark 1.2 or Solar Pro 4?
Muse Spark 1.2 is the better all-round choice, scoring 60/100 against Solar Pro 4 (55) and GLM-5.3 (43). It leads on inputs & features. Solar Pro 4 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-5.3, Muse Spark 1.2 or Solar Pro 4?
Solar Pro 4 is cheaper at $0.30 input / $1.20 output per million tokens (official Upstage API price). Muse Spark 1.2 costs $1.25 input / $4.25 output per million tokens (official Meta 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 $2.00 for Muse Spark 1.2 (3.8× as much) and $2.15 for GLM-5.3 (4.1× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. GLM-5.3 has an ECI of 155.8, Muse Spark 1.2 has an ECI of 155.0 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, Muse Spark 1.2 and Solar Pro 4 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?
Muse Spark 1.2 has the largest context window at 1,048,576 tokens, against 1,000,000 for GLM-5.3 and 524,288 for Solar Pro 4. Maximum output per response: GLM-5.3 up to 131,072, Muse Spark 1.2 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; Muse Spark 1.2 accepts text, images, PDFs, audio and video; Solar Pro 4 accepts text. Muse Spark 1.2 handles the widest range of inputs.
Are any of these open source?
GLM-5.3 publishes its weights and can be self-hosted; Muse Spark 1.2 and 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; Muse Spark 1.2 came out Aug 5, 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.
