GPT-5.3 Chat vs Grok 4.20 (Non-Reasoning) vs MiMo-V2-Pro
Grok 4.20 (Non-Reasoning) comes out ahead, 52 to 42 and 28 on our weighted score.
OpenAIGPT-5.3 Chat
28/100- ECI—
- Price$1.75 / $14.00
- Context128K
- Our pick
xAIGrok 4.20 (Non-Reasoning)
52/100- ECI—
- Price$1.25 / $2.50
- Context1M
XiaomiMiMo-V2-Pro
42/100- ECI—
- Price$1.00 / $3.00
- Context1.05M
Grok 4.20 (Non-Reasoning) is our pick
Grok 4.20 (Non-Reasoning) is the better all-round choice, scoring 52/100 against MiMo-V2-Pro (42) and GPT-5.3 Chat (28). 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 priceMiMo-V2-ProMiMo-V2-Pro $1.50 · Grok 4.20 (Non-Reasoning) $1.56 · GPT-5.3 Chat $4.81 per 1M tokens (3:1 blend)
- Longest contextMiMo-V2-ProMiMo-V2-Pro 1,048,576 · Grok 4.20 (Non-Reasoning) 1,000,000 · GPT-5.3 Chat 128,000 tokens
- Widest inputsGrok 4.20 (Non-Reasoning)GPT-5.3 Chat: Text, Images · Grok 4.20 (Non-Reasoning): Text, Images, PDFs · MiMo-V2-Pro: Text
- Self-hostingNo open weightsAll three are available only through APIs
| Measure | Weight | GPT-5.3 Chat | Grok 4.20 (Non-Reasoning) | MiMo-V2-Pro |
|---|---|---|---|---|
| Price | 50% | 17 | 39 | 40 |
| Inputs & features | 30% | 50 | 70 | 35 |
| Context window | 20% | 24 | 60 | 61 |
| Overall | 100% | 28/100 | 52/100 | 42/100 |
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 | GPT-5.3 ChatOpenAI | Grok 4.20 (Non-Reasoning)xAI | MiMo-V2-ProXiaomi |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | — | — | — |
| ECI rank | — | — | — |
| Price per million tokens | |||
| Input | $1.75 | $1.25 | $1.00 (best) |
| Output | $14.00 | $2.50 (best) | $3.00 |
| Cached input | — | $0.20 | — |
| Blended (3:1) | $4.81 | $1.56 | $1.50 (best) |
| Long-context rate | Same rate | Over 200K: $2.50 / $5.00 | Same rate |
| Price source | Median of 4 providers | Official xAI API | Median of 1 providers |
| Limits | |||
| Context window | 128,000 tokens | 1,000,000 tokens | 1,048,576 tokens (best) |
| Max output | 16,384 tokens | 30,000 tokens | 131,072 tokens (best) |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | No |
| PDFs | No | Yes | No |
| Audio | No | No | No |
| Video | No | No | No |
| Reasoning | No | No | Yes |
| Tool calling | Yes | Yes | Yes |
| Structured output | No | Yes | No |
| Availability | |||
| Weights | Proprietary | Proprietary | Proprietary |
| API model ID | — | grok-4.20-0309-non-reasoning | — |
| API providers | 4 | 13 (best) | 2 |
| Released | Mar 3, 2026 | Mar 9, 2026 | Mar 18, 2026 |
| Knowledge cutoff | Aug 31, 2025 | — | Dec 2024 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- GPT-5.3 Chat$45.50
- Grok 4.20 (Non-Reasoning)$17.50
- MiMo-V2-Pro$16.00
Which should you choose?
Which is better: GPT-5.3 Chat, Grok 4.20 (Non-Reasoning) or MiMo-V2-Pro?
Grok 4.20 (Non-Reasoning) is the better all-round choice, scoring 52/100 against MiMo-V2-Pro (42) and GPT-5.3 Chat (28). 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, GPT-5.3 Chat, Grok 4.20 (Non-Reasoning) or MiMo-V2-Pro?
MiMo-V2-Pro is cheaper at $1.00 input / $3.00 output per million tokens (median across 1 API provider). Grok 4.20 (Non-Reasoning) costs $1.25 input / $2.50 output per million tokens (official xAI API price); GPT-5.3 Chat costs $1.75 input / $14.00 output per million tokens (median across 4 API providers). At a typical mix of three input tokens to one output token, that is $1.50 per million tokens for MiMo-V2-Pro versus $1.56 for Grok 4.20 (Non-Reasoning) (1× as much) and $4.81 for GPT-5.3 Chat (3.2× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. GPT-5.3 Chat has not been scored yet, Grok 4.20 (Non-Reasoning) has not been scored yet and MiMo-V2-Pro has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for GPT-5.3 Chat, Grok 4.20 (Non-Reasoning) and MiMo-V2-Pro 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?
MiMo-V2-Pro has the largest context window at 1,048,576 tokens, against 1,000,000 for Grok 4.20 (Non-Reasoning) and 128,000 for GPT-5.3 Chat. Maximum output per response: GPT-5.3 Chat up to 16,384, Grok 4.20 (Non-Reasoning) up to 30,000, MiMo-V2-Pro up to 131,072 tokens.
Which can read images, PDFs, audio or video?
GPT-5.3 Chat accepts text and images; Grok 4.20 (Non-Reasoning) accepts text, images and PDFs; MiMo-V2-Pro accepts text. Grok 4.20 (Non-Reasoning) handles the widest range of inputs.
Are any of these open source?
No. GPT-5.3 Chat, Grok 4.20 (Non-Reasoning) and MiMo-V2-Pro are proprietary and only available through APIs and apps.
Which is newer?
MiMo-V2-Pro is the newest, released Mar 18, 2026. Grok 4.20 (Non-Reasoning) came out Mar 9, 2026; GPT-5.3 Chat came out Mar 3, 2026. Knowledge cutoff: GPT-5.3 Chat Aug 31, 2025, MiMo-V2-Pro Dec 2024.
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.
