ZMIME
Comparison · 2 models · Updated Nov 2, 2026

Grok 4 Fast Non Reasoning vs Solar Pro 3

Grok 4 Fast Non Reasoning comes out ahead, 72 to 53 on our weighted score, though Solar Pro 3 is 9% cheaper per token.

  1. Our pick

    xAI

    Grok 4 Fast Non Reasoning

    Released Dec 18, 2025

    72/100
    • ECI—
    • Price$0.20 / $0.50
    • Context2M
  2. Upstage

    Solar Pro 3

    Released Jan 26, 2026

    53/100
    • ECI—
    • Price$0.25 / $0.25
    • Context131K
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Grok 4 Fast Non Reasoning is our pick

Grok 4 Fast Non Reasoning is the better all-round choice, scoring 72/100 against Solar Pro 3 (53). It leads on inputs & features and context window. Solar Pro 3 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 3Solar Pro 3 $0.25 · Grok 4 Fast Non Reasoning $0.275 per 1M tokens (3:1 blend)
  • Longest contextGrok 4 Fast Non ReasoningGrok 4 Fast Non Reasoning 2,000,000 · Solar Pro 3 131,072 tokens
  • Widest inputsGrok 4 Fast Non ReasoningGrok 4 Fast Non Reasoning: Text, Images, Audio, Video · Solar Pro 3: Text
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGrok 4 Fast Non ReasoningSolar Pro 3
Price50%7375
Inputs & features30%7035
Context window20%7225
Overall100%72/10053/100

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.

Grok 4 Fast Non Reasoning vs Solar Pro 3 specifications side by side
SpecificationGrok 4 Fast Non ReasoningxAISolar Pro 3Upstage
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$0.20 (best)$0.25
Output$0.50$0.25 (best)
Cached input——
Blended (3:1)$0.275$0.25 (best)
Long-context rateSame rateSame rate
Price sourceMedian of 7 providersOfficial Upstage API
Limits
Context window2,000,000 tokens (best)131,072 tokens
Max output2,000,000 tokens (best)8,192 tokens
Inputs and features
TextYesYes
ImagesYesNo
PDFsNoNo
AudioYesNo
VideoYesNo
ReasoningNoYeslow · medium · high
Tool callingYesYes
Structured outputNoNo
Availability
WeightsProprietaryProprietary
API model ID—solar-pro3
API providers8 (best)4
ReleasedDec 18, 2025Jan 26, 2026
Knowledge cutoff—Jul 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.

  • Grok 4 Fast Non Reasoning$3.00
  • Solar Pro 3$3.00
04 — Questions

Which should you choose?

Which is better: Grok 4 Fast Non Reasoning or Solar Pro 3?

Grok 4 Fast Non Reasoning is the better all-round choice, scoring 72/100 against Solar Pro 3 (53). It leads on inputs & features and context window. Solar Pro 3 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, Grok 4 Fast Non Reasoning or Solar Pro 3?

Solar Pro 3 is cheaper at $0.25 input / $0.25 output per million tokens (official Upstage API price). Grok 4 Fast Non Reasoning costs $0.20 input / $0.50 output per million tokens (median across 7 API providers). At a typical mix of three input tokens to one output token, that is $0.25 per million tokens for Solar Pro 3 versus $0.275 for Grok 4 Fast Non Reasoning (1.1× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. Grok 4 Fast Non Reasoning has not been scored yet and Solar Pro 3 has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4 Fast Non Reasoning and Solar Pro 3 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?

Grok 4 Fast Non Reasoning has the largest context window at 2,000,000 tokens, against 131,072 for Solar Pro 3. Maximum output per response: Grok 4 Fast Non Reasoning up to 2,000,000, Solar Pro 3 up to 8,192 tokens.

Which can read images, PDFs, audio or video?

Grok 4 Fast Non Reasoning accepts text, images, audio and video; Solar Pro 3 accepts text. Grok 4 Fast Non Reasoning handles the widest range of inputs.

Are any of these open source?

No. Grok 4 Fast Non Reasoning and Solar Pro 3 are proprietary and only available through APIs and apps.

Which is newer?

Solar Pro 3 is the newest, released Jan 26, 2026. Grok 4 Fast Non Reasoning came out Dec 18, 2025. Knowledge cutoff: Solar Pro 3 Jul 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 Nov 2, 2026.