GPT-5.5 vs MiMo-V2.5

OpenAI · US  |  Xiaomi · China · Updated June 2026

Quick verdict

Pick GPT-5.5 for terminal, cli and computer-use automation or long-horizon tool sequencing. Pick MiMo-V2.5 for native omnimodal — strong image and video understanding or very low cost (~half the inference of the pro tier). Choose MiMo-V2.5 if you need self-hosting or data privacy; GPT-5.5 if you want a managed API.

GPT-5.5 (OpenAI, US) and MiMo-V2.5 (Xiaomi, China) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. GPT-5.5 is openAI's first fully retrained base since GPT-4.5 — the terminal and computer-use champion. MiMo-V2.5 is xiaomi's cheap omnimodal model — Pro-level agentic perception across image and video at a fraction of the cost. They diverge most on price and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecGPT-5.5MiMo-V2.5
ProviderOpenAI (US) Xiaomi (China)
ReleasedApril 23, 2026 April 22, 2026
Context window1M (~1,500 pages) 1M (~1,500 pages)
Price (in/out)$5/$30 per 1M tokens $0.14/$0.28 per 1M tokens
Open weight?No — API only Yes — self-hostable
Modalitiestext, image, audio, video, code text, image, audio, video, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Terminal, CLI and computer-use automation

GPT-5.5

A core design strength of GPT-5.5.

Long-horizon tool sequencing

GPT-5.5

A core design strength of GPT-5.5.

Natively omnimodal input

GPT-5.5

A core design strength of GPT-5.5.

Native omnimodal — strong image and video understanding

MiMo-V2.5

A core design strength of MiMo-V2.5.

Very low cost (~half the inference of the Pro tier)

MiMo-V2.5

A core design strength of MiMo-V2.5.

Agent-framework integration

MiMo-V2.5

A core design strength of MiMo-V2.5.

Lowest cost at scale

MiMo-V2.5

At $0.14/$0.28 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Which should you pick?

A cost-sensitive startup shipping high volume

MiMo-V2.5

At $0.14/$0.28 per 1M tokens it undercuts GPT-5.5, and on millions of tokens that margin decides the monthly bill.

A team with data-privacy or self-hosting needs

MiMo-V2.5

Open weights let you run it on your own hardware; GPT-5.5 is API-only.

Anyone whose priority is terminal, cli and computer-use automation

GPT-5.5

It is specifically built for that.

Anyone whose priority is native omnimodal — strong image and video understanding

MiMo-V2.5

That is its strongest area.

An enterprise with regional data-residency rules

GPT-5.5 or MiMo-V2.5

Origin (US vs China) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

GPT-5.5: where it fits

OpenAI's first fully retrained base since GPT-4.5 — the terminal and computer-use champion. Released April 23, 2026 by OpenAI, it is built for terminal, CLI and computer-use automation, long-horizon tool sequencing, natively omnimodal input, and browser-driving agents.

Its trade-offs are real: trails Opus 4.8 on hardest coding benchmarks, and tiered long-context pricing above 272K tokens. At $5 in / $30 out per million tokens, it sits in the premium price band.

MiMo-V2.5: where it fits

Xiaomi's cheap omnimodal model — Pro-level agentic perception across image and video at a fraction of the cost. Released April 22, 2026 by Xiaomi, it is built for native omnimodal — strong image and video understanding, very low cost (~half the inference of the Pro tier), agent-framework integration, and 1M context for full documents in one pass.

Its trade-offs: not the deepest reasoning tier (see V2.5-Pro), and limited Western tooling and support. At $0.14 in / $0.28 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

The defining split here is open vs. closed. MiMo-V2.5 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. GPT-5.5 gives you a managed, always-updated API with no infrastructure to run. Teams with GPUs, privacy requirements, or huge volume often favour the open model; teams that want zero ops and the latest capabilities favour the closed one. Capability is close enough that this operational question, not the benchmark, usually decides it.

Want both GPT-5.5 and MiMo-V2.5 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is GPT-5.5 or MiMo-V2.5 better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, GPT-5.5 leans toward terminal, cli and computer-use automation while MiMo-V2.5 leans toward native omnimodal — strong image and video understanding, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-5.5 or MiMo-V2.5?

MiMo-V2.5 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while GPT-5.5 is API-metered at $5/$30 per 1M tokens. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

Both advertise 1M (~1,500 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both GPT-5.5 and MiMo-V2.5 together?

Yes — a multi-model platform like LumiChats gives you GPT-5.5, MiMo-V2.5 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, GPT-5.5 or MiMo-V2.5?

GPT-5.5 — released April 23, 2026, about 1 days after MiMo-V2.5.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.