GPT-6 Sol vs MiMo-V2.5-Pro

OpenAI · US  |  Xiaomi · China · Updated June 2026

Quick verdict

Pick GPT-6 Sol for openai's everyday-work tier below gpt-6 astra, built with the same methods that improved astra's professional work, factuality, coding, computer use, and alignment or openai says it makes about half as many mistakes as gpt-5.6 sol. Pick MiMo-V2.5-Pro for complex software engineering (top-ranked on swe-bench pro) or long-horizon autonomous tasks (1,000+ tool calls). Choose MiMo-V2.5-Pro if you need self-hosting or data privacy; GPT-6 Sol if you want a managed API.

GPT-6 Sol (OpenAI, US) and MiMo-V2.5-Pro (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-6 Sol is openAI's September 22, 2026 mid-tier update — Astra-derived improvements at half the GPT-5.6 Sol price, $2/$10 per million tokens. MiMo-V2.5-Pro is xiaomi's flagship agentic model — autonomous, long-horizon software engineering at a fraction of frontier cost. They diverge most on price, context window and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecGPT-6 SolMiMo-V2.5-Pro
ProviderOpenAI (US) Xiaomi (China)
ReleasedSeptember 22, 2026 April 22, 2026
Context window1.05M tokens (~1,575 pages) 1M (~1,500 pages)
Price (in/out)$2/$10 per 1M tokens $0.435/$0.87 per 1M tokens
Open weight?No — API only Yes — self-hostable
Modalitiestext, image text, image, video, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

OpenAI's everyday-work tier below GPT-6 Astra, built with the same methods that improved Astra's professional work, factuality, coding, computer use, and alignment

GPT-6 Sol

OpenAI's September 22, 2026 mid-tier update — Astra-derived improvements at half the GPT-5.6 Sol price, $2/$10 per million tokens — and it is the newer of the two.

OpenAI says it makes about half as many mistakes as GPT-5.6 Sol

GPT-6 Sol

GPT-6 Sol lists openAI says it makes about half as many mistakes as GPT-5.6 Sol among its strengths; MiMo-V2.5-Pro does not.

Priced at half of the GPT-5.6 Sol/Luna generation's rates ($2/$10 vs GPT-5.6 Sol's $5/$30)

GPT-6 Sol

GPT-6 Sol lists priced at half of the GPT-5.6 Sol/Luna generation's rates ($2/$10 vs GPT-5.6 Sol's $5/$30) among its strengths; MiMo-V2.5-Pro does not.

Complex software engineering (top-ranked on SWE-bench Pro)

MiMo-V2.5-Pro

Xiaomi's flagship agentic model — autonomous, long-horizon software engineering at a fraction of frontier cost — and it runs cheaper at $0.435/$0.87 per 1M tokens.

Long-horizon autonomous tasks (1,000+ tool calls)

MiMo-V2.5-Pro

Xiaomi's flagship agentic model — autonomous, long-horizon software engineering at a fraction of frontier cost — and its weights are open while GPT-6 Sol is API-only.

Strong on GDPVal and ClawEval

MiMo-V2.5-Pro

MiMo-V2.5-Pro lists strong on GDPVal and ClawEval among its strengths; GPT-6 Sol does not.

Lowest cost at scale

MiMo-V2.5-Pro

At $0.435/$0.87 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-Pro

At $0.435/$0.87 per 1M tokens it undercuts GPT-6 Sol, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

GPT-6 Sol

Larger 1.05M tokens window fits more in one prompt.

A team with data-privacy or self-hosting needs

MiMo-V2.5-Pro

Open weights let you run it on your own hardware; GPT-6 Sol is API-only.

Anyone whose priority is openai's everyday-work tier below gpt-6 astra, built with the same methods that improved astra's professional work, factuality, coding, computer use, and alignment

GPT-6 Sol

It is specifically built for that.

Anyone whose priority is complex software engineering (top-ranked on swe-bench pro)

MiMo-V2.5-Pro

That is its strongest area.

An enterprise with regional data-residency rules

GPT-6 Sol or MiMo-V2.5-Pro

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

GPT-6 Sol: where it fits

OpenAI's September 22, 2026 mid-tier update — Astra-derived improvements at half the GPT-5.6 Sol price, $2/$10 per million tokens. Released September 22, 2026 by OpenAI, it is built for openAI's everyday-work tier below GPT-6 Astra, built with the same methods that improved Astra's professional work, factuality, coding, computer use, and alignment, openAI says it makes about half as many mistakes as GPT-5.6 Sol, priced at half of the GPT-5.6 Sol/Luna generation's rates ($2/$10 vs GPT-5.6 Sol's $5/$30), and 1.05M-token context window, input capped at 922K.

Its trade-offs are real: more reasoning capability than sibling GPT-6 Luna, but still positioned below flagship GPT-6 Astra, and cache-read pricing ($0.20/MTok) still costlier than Luna's ($0.01/MTok) for high-cache workloads. At $2 in / $10 out per million tokens, it sits in the mid price band.

MiMo-V2.5-Pro: where it fits

Xiaomi's flagship agentic model — autonomous, long-horizon software engineering at a fraction of frontier cost. Released April 22, 2026 by Xiaomi, it is built for complex software engineering (top-ranked on SWE-bench Pro), long-horizon autonomous tasks (1,000+ tool calls), strong on GDPVal and ClawEval, and agent-framework integration.

Its trade-offs: benchmark rankings are largely vendor-stated, and limited Western adoption and tooling. At $0.435 in / $0.87 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-Pro gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. GPT-6 Sol 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-6 Sol and MiMo-V2.5-Pro 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-6 Sol or MiMo-V2.5-Pro 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-6 Sol leans toward openai's everyday-work tier below gpt-6 astra, built with the same methods that improved astra's professional work, factuality, coding, computer use, and alignment while MiMo-V2.5-Pro leans toward complex software engineering (top-ranked on swe-bench pro), and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-6 Sol or MiMo-V2.5-Pro?

MiMo-V2.5-Pro is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while GPT-6 Sol is API-metered at $2/$10 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?

Effectively neither — 1.05M tokens vs 1M is a difference of a few percent. Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both GPT-6 Sol and MiMo-V2.5-Pro together?

Yes — a multi-model platform like LumiChats gives you GPT-6 Sol, MiMo-V2.5-Pro 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-6 Sol or MiMo-V2.5-Pro?

GPT-6 Sol — released September 22, 2026, about 5 months after MiMo-V2.5-Pro.

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.