Model comparison
GPT-5.5 vs Xiaomi MiMo-V2.5-Pro
OpenAI against Xiaomi, compared on context, price, and verified benchmark results.
Catalog record checked September 3, 2026Individual provider fields may changeEvidence confidence: High — see receipts below
OpenAI
GPT-5.5
Frontier
Xiaomi
Xiaomi MiMo-V2.5-Pro
Frontier · Open weights
| Specification | GPT-5.5 | Xiaomi MiMo-V2.5-Pro |
|---|---|---|
| Provider | OpenAI | Xiaomi |
| Tier | Frontier | Frontier |
| Context window | Winner: 1.05M | 1M |
| Max output | 128K | Not verifiedUnverified |
| Input / 1M tokens | $5 | Winner: $1 |
| Output / 1M tokens | $30 | Winner: $3 |
| Weights | Closed | Open |
| Parameters | Not disclosedUnverified | 1.02T total / 42B active (MoE) |
| Reasoning levels | none, low, medium, high, xhigh, max | low, high, max |
| Modalities | text, image | text, image |
| License | Not disclosedUnverified | MIT |
| API model id | gpt-5.5 | mimo-v2-5-pro |
| Released | April 23, 2026 | April 22, 2026 |
| Artificial Analysis Intelligence Index [xhigh] (2026-08-14) | 58 | Not verifiedUnverified |
| Artificial Analysis Intelligence Index (2026-08-14) | Not verifiedUnverified | 52 |
| SWE-bench Verified (2026-09-01) | 82.6 | Not verifiedUnverified |
| Terminal-Bench 2.1 (2026-07-27) | 83.4 | Not verifiedUnverified |
| GPQA Diamond (2026-07-27) | 93.5 | Not verifiedUnverified |
| Humanity's Last Exam (2026-04-23) | 52.2 | Not verifiedUnverified |
Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.
Benchmark receipts
- 2026-09-01: vals.ai SWE-bench Verified leaderboard (independent, mini-swe-agent bash-only); official SWE-bench not publishedReal GitHub issue resolution: does the model's patch pass the hidden tests. Comparability: comparable with caveat — Post-audit vendor claims and pre-audit scores sit on different task trust levels; scaffolding (agent harness, compute budget) also dominates results. Never aggregate across scaffolds.
- 2026-08-14: Artificial AnalysisComposite index blending reasoning, knowledge, and coding evals into one 0–100 score. Comparability: directly comparable — AA occasionally rebaselines the index scale between snapshots — a score captured on one date is only comparable to same-snapshot scores (check measuredAt).
- 2026-07-27: Kimi K3 model card (vendor-reported, xhigh); announcement charts show 93.6 — minor conflict preservedAgentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.
- 2026-04-23: OpenAI — Introducing GPT-5.5 (vendor, with tools; 41.4 no tools)Frontier-knowledge ceiling: extremely hard multi-domain questions written to be near-impossible without deep expertise. Comparability: comparable with caveat — Subset/tool configurations (text-only vs with-tools) differ between vendors and materially change scores; must match configuration to compare.
Pricing tiers: GPT-5.5: Standard $5/$30 per MTok; >272K input billed 2x in / 1.5x out. Cached input $0.50/MTok; batch $2.50/$15. · Xiaomi MiMo-V2.5-Pro: $1.00/$3.00 per MTok up to 256K prompt; $2.00/$6.00 above 256K (to 1M). Open weights (MIT). 1.02T/42B active MoE, native multimodal.
GPT-5.5
GPT-5.5 is OpenAI's previous flagship — strong on Terminal-Bench 2.0 (82.7%) and 1M-token context.
Best for
- Reasoning
- Agentic coding
- Long-context work
Watch out
Superseded by GPT-5.6 Sol on quality; still a capable, widely integrated model.
Xiaomi MiMo-V2.5-Pro
MiMo-V2.5-Pro is Xiaomi's open-weight (MIT) 1.02T MoE with native multimodal and a 1M context.
Best for
- Open-weight frontier
- Multimodal
- Long-context
Watch out
Verify weights/pricing on your endpoint.
When the cheaper one wins
Xiaomi MiMo-V2.5-Pro is cheaper on output at $3 per million tokens against $30 for GPT-5.5 — about 10×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.
Run the model pickerEvidence confidence: High
How strong and complete the evidence behind this comparison is — not a prediction of which model is better.
- Pricing verified on both sides — Input and output rates are verified for both models.
- 3/5 core specs verified on both sides — Not published for at least one side: max output, parameter count.
- 1 shared named benchmark with differing scores — Measured on: Artificial Analysis Intelligence Index.
- Verified within the last 90 days — Newest catalog check was 8 days ago.
- Both models carry source citations — Each side has at least two catalog sources on record.
Source receipts
Each catalog figure was checked against the provider or an independent second source on the date shown.
- GPT-5.5: OpenAI — Introducing GPT-5.5 (accessed 2026-08-29)
- GPT-5.5: OpenAI API pricing (gpt-5.5 $5/$30) (accessed 2026-08-29)
- Xiaomi MiMo-V2.5-Pro: Xiaomi — MiMo V2.5 (accessed 2026-08-29)
- Xiaomi MiMo-V2.5-Pro: Xiaomi MiMo (accessed 2026-08-29)
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Diving deeper on one model? GPT-5.5 · Xiaomi MiMo-V2.5-Pro
Common questions
GPT-5.5 vs Xiaomi MiMo-V2.5-Pro
Answered from the verified figures on this page rather than general guidance.
Is GPT-5.5 or Xiaomi MiMo-V2.5-Pro cheaper for input?
Xiaomi MiMo-V2.5-Pro is cheaper at $1 per million input tokens, against $5 for GPT-5.5 — roughly 5.0× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; GPT-5.5 has tiered pricing: Standard $5/$30 per MTok; >272K input billed 2x in / 1.5x out. Cached input $0.50/MTok; batch $2.50/$15. Xiaomi MiMo-V2.5-Pro has tiered pricing: $1.00/$3.00 per MTok up to 256K prompt; $2.00/$6.00 above 256K (to 1M). Open weights (MIT). 1.02T/42B active MoE, native multimodal.
Is GPT-5.5 or Xiaomi MiMo-V2.5-Pro cheaper for output?
Xiaomi MiMo-V2.5-Pro is cheaper at $3 per million output tokens, against $30 for GPT-5.5 — roughly 10× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; GPT-5.5 has tiered pricing: Standard $5/$30 per MTok; >272K input billed 2x in / 1.5x out. Cached input $0.50/MTok; batch $2.50/$15. Xiaomi MiMo-V2.5-Pro has tiered pricing: $1.00/$3.00 per MTok up to 256K prompt; $2.00/$6.00 above 256K (to 1M). Open weights (MIT). 1.02T/42B active MoE, native multimodal.
Which has the larger context window, GPT-5.5 or Xiaomi MiMo-V2.5-Pro?
GPT-5.5 accepts 1.05M tokens against 1M for Xiaomi MiMo-V2.5-Pro. This only matters if you routinely send very long documents or large codebases.
Do GPT-5.5 and Xiaomi MiMo-V2.5-Pro support the same reasoning levels?
GPT-5.5 exposes none, low, medium, high, xhigh, max, while Xiaomi MiMo-V2.5-Pro exposes low, high, max.
Should I use GPT-5.5 or Xiaomi MiMo-V2.5-Pro?
Both sit in the frontier tier, so the choice usually comes down to price and context rather than capability. GPT-5.5 suits reasoning; Xiaomi MiMo-V2.5-Pro suits open-weight frontier.
Can I self-host GPT-5.5 or Xiaomi MiMo-V2.5-Pro?
Xiaomi MiMo-V2.5-Pro publishes open weights, but self-hosting and third-party provider access depend on the licence, hardware, serving support, and availability. GPT-5.5 is a closed model whose supported access paths are controlled by its provider.
Next step
Choosing between them
The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.
- Input price: Xiaomi MiMo-V2.5-Pro costs $1 per 1M tokens versus $5 for GPT-5.5 — a 5x difference at the headline tier.
- Context: GPT-5.5 takes 1.05M against 1M for Xiaomi MiMo-V2.5-Pro — only decisive if your prompts approach the smaller window.
- Measured capability: GPT-5.5 leads Artificial Analysis Intelligence Index 58 to 52 (measured 2026-08-14).
- Deployment: Xiaomi MiMo-V2.5-Pro publishes weights you can self-host; the other is API-only.
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