Xiaomi open-sources MiMo-V2.6, topping open-weight leaderboard at 46 with livestreamed RL training

On September 22, Xiaomi open-sourced the MiMo-V2.6 fully multimodal model series on Hugging Face under the MIT license. The Pro model scored 46 on the Artificial Analysis Intelligence Index, topping the open-weight leaderboard for the first time—a large jump from MiMo-V2.5-Pro's 26 and only about 1 point behind GPT-5.6 Sol. The team also released the tech report, RL environments and training code, livestreamed the entire training run, and cited roughly $3.5M in total training cost, with the report breaking out $2.6M for Pro's RL stage and $0.9M for Flash. It was the most-watched open-source event of the day.

Confirmed

• Two flagship models: MiMo-V2.6-Pro with 1.02T total / 42B active parameters, and MiMo-V2.6-Flash with 310B total / 15B active—both Sparse MoE, natively multimodal (text/image/video/audio), 1M-token context, MIT-licensed (cross-confirmed by @natolambert, @ArtificialAnlys and others)
• Pro scored 46 on the AA Intelligence Index, the top open-weight model; predecessor MiMo-V2.5-Pro scored 26 (@ArtificialAnlys); per @heyshrutimishra citing AA rankings, Pro's weighted cost is about $0.13 per task
• Architecture unchanged from V2.5, adding a 1M-token context window and an MTP drafter; early evaluations show scores just behind GPT-5.6 Sol (@mervenoyann)
• Beyond weights, the tech report, RL environments and training code are open-sourced, with 7000 RL training environments planned; the official claim is that Pro matches Claude Opus 5 / GPT-5.6 Sol-class models on most agent benchmarks and entered the Code Arena top 10 (@arena, @teortaxesTex)
• API pricing is unchanged from V2.5 for both Pro and Flash; officially claimed to set a new cost-performance record for Chinese models at 1/20 to 1/60 of international pricing (official line via @amaarora)
• Per @wearemammals relaying official figures, total training cost was about $3.5M, positioned for extreme cost-effectiveness, with a live benchmarking dashboard publicly tracking evaluations; training was livestreamed (@Prompt Engineering)
• The tech report details: $2.6M for Pro's RL training, $0.9M for Flash, with 44% of compute on rollouts (via @KyeGomezB); @andersonbcdefg relays AA's report that 45k RL tasks cost about $2.6M; @pcuenq notes per-task cost is a small fraction of peers, and the RL livestream has ended
• Luo Fuli wrote a long post: amid extreme compute scarcity, Xiaomi committed a team of dozens to scaling up RL long-term, with a mid-training approach—likely the largest single RL run by compute among open-source teams, harder than DeepSeek R1 (relayed by @timshiai, @teortaxesTex)
• @deedydas tested MiMo 2.6 Pro hands-on, found it quite good and willing to answer security-research questions, estimating agentic-coding pricing (with cache-hit assumptions) at 15x cheaper than Kimi K3, 6x cheaper than GLM 5.3, and about half of DeepSeek V4
• @TheAhmadOsman (relayed by @Jasonio) noted Pro is only 1 point below GPT 5.6 Sol Max yet runs on 8x RTX PRO 6000
• Reddit discussion (@power97992) regards MiMo 2.6 Pro as the strongest open model on aggregate benchmarks, lists Xiaomi, Z-AI and Kimi as the leading Chinese labs, but notes real-world usage still has misses; @arpitbhayani also called it much better than other models, surprised Xiaomi wasn't on his watchlist
• The Hugging Face repos include MiMo-V2.6-Distill-Qwen-9B (image-text-to-text distilled) alongside Pro-RL and Flash-RL (@Bestlife73, @AdinaYakup); MiMo-V2.6-Flash-RL hit the Hugging Face trending list (@XiaomiMiMo)
• @tokenbender observed from Flash-RL's config that it supports image, audio and video inputs with built-in tool-call rendering templates for agent workflows
• Per @natolambert and @giffmana's discussion, the MiMo team released the model within about a day of finishing RL training

Unconfirmed

• @mervenoyann noted AA benchmark scores were incomplete at release; @victormustar cited 524B parameters for Pro, inconsistent with most posts' 1.02T total—check the model page; the $3.5M total cost vs $2.6M (Pro RL stage) figures differ—given the report's $2.6M/$0.9M split, the former likely includes pretraining while the latter covers RL only

Why it matters

• A phone maker's model topping the third-party intelligence index for open weights, with trillion-parameter weights and RL training code fully released, materially shifts the open-source landscape
• The jump from 26 to 46 sets what @victormustar calls a new open-model record on the index; the RL scale described by Luo Fuli, the relatively low $3.5M total cost, the livestreamed training and 7000 planned open RL environments are seen by the community as a signal that large-scale RL is becoming reproducible by anyone
• API pricing held at V2.5 levels, reinforced by @deedydas's hands-on cost estimates and the $0.13 per-task weighted cost, strengthening the cost-performance claim

2026-09-22 ~ 2026-09-23 · 47 related posts

Full story(4 episodes)→

• Episode 1: Xiaomi MiMo Finishes RL Training, DeepSWE Score Jumps to 72.57(2026-09-21, 2 posts)
• Episode 2: Xiaomi open-sources MiMo-V2.6, topping open-weight leaderboard at 46 with livestreamed RL training(2026-09-22, 47 posts)
• Episode 3: Xiaomi's MiMo-V2.6 Pro tested: big gains in coding, 3D games and multimodal(2026-09-22, 2 posts)
• Episode 4: Xiaomi Open-Sources MiMo-V2.6, Scoring 46 on AA Index, Just 1 Point Behind GPT-5.6(2026-09-24, 7 posts)

• [source] MiMo-V2.6 launches: 1.02T-param MoE claims top open model spot — natolambert · 2026-09-22
• MiMo-V2.6 launches: 1.02T-param open model tops Artificial Analysis open rankings — natolambert · 2026-09-22
• Xiaomi releases MiMo-V2.6-Flash-RL on Hugging Face — Bestlife73 · 2026-09-22
• [source] Xiaomi's open-weights MiMo-V2.6-Pro tops Artificial Analysis index with 1T-param MoE at $0.13/task — ArtificialAnlys · 2026-09-22
• Xiaomi open-sources MiMo-V2.6 omni-modal models, topping open-model index at 46.32 — victormustar · 2026-09-22
• Xiaomi releases MiMo-V2.6-Flash-RL weights on Hugging Face — tokenbender · 2026-09-22
• Xiaomi ships MiMo-V2.6 with 1M context, scores just behind GPT-5.6 Sol — mervenoyann · 2026-09-22
• Xiaomi's open MiMo-V2.6 tops Artificial Analysis open-model index — pcuenq · 2026-09-22
• Xiaomi open-sources MiMo-V2.6: MoE models with 1M context, MIT license — AdinaYakup · 2026-09-22
• MiMo-V2.6 lands on Hugging Face with Pro-RL, Flash-RL and 9B distill — AdinaYakup · 2026-09-22
• Xiaomi's MiMo-V2.6-Pro debuts as top open-weights model with ~$2.6m RL training bill — andersonbcdefg · 2026-09-22
• Xiaomi MiMo-V2.6 lands, jumping 153 pts to crack Code Arena top 10 among open weights — arena · 2026-09-22
• MiMo V2.6 ships, team plans to open source 7,000 RL environments — teortaxesTex · 2026-09-22
• Reddit debate: Xiaomi's Mimo 2.6 Pro tops open benchmarks as Chinese labs lead — power97992 · 2026-09-22
• Xiaomi's MiMo-V2.6-Flash-RL trends on Hugging Face with multimodal and agent skills — XiaomiMiMo · 2026-09-22
• MiMo-V2.6 billed as largest single open-source RL run, harder than R1 — teortaxesTex · 2026-09-22
• Shots fired at DeepSeek: MiMo pioneered MOPD, observers weigh in on V2.6 — teortaxesTex · 2026-09-22
• Xiaomi open-sources MiMo-V2.6: 1.02T-param Pro brings near-frontier multimodal reasoning — teortaxesTex · 2026-09-22
• Xiaomi releases open-source MiMo-V2.6-Pro and Flash, claiming parity with Claude Opus 5 — airesearch12 · 2026-09-22
• Xiaomi releases MiMo-V2.6 omnimodal open models, top open-source on AA Index at 46 — Scobleizer · 2026-09-22
• Xiaomi Open-Sources MiMo-V2.6 After a $3.47M RL Run, Claims Top Open-Model Score — APPSO · 2026-09-22
• Xiaomi's MiMo-V2.6 Likely the Largest Single RL Run by an Open-Source Team, Now Top Open Model — timshi_ai · 2026-09-22
• Xiaomi MiMo 2.6 Pro hands-on: 2x cheaper than DeepSeek V4, refuses no cybersecurity queries — deedydas · 2026-09-22
• Xiaomi's Mimo 2.6 Pro claims best open-source model, 15x cheaper than Kimi K3 — deedydas · 2026-09-22
• Xiaomi releases MiMo-V2.6 with all modalities for just $3.5M in training cost — we_are_mammals · 2026-09-22
• Xiaomi's $3.5M livestreamed RL run ends: MiMo-V2.6-Pro takes open-source crown — 量子位 · 2026-09-22
• Xiaomi ships MiMo-V2.6 at unchanged prices, claiming 1/20-1/60 the cost of leading international models — amaarora · 2026-09-22
• MiMo-V2.6-Pro: 42B-active open model nears GPT 5.6, runs on 8x RTX PRO 6000 — Jasonio · 2026-09-22
• Xiaomi launches open-source MiMo-2.6 model series, praised as outperforming rivals — arpit_bhayani · 2026-09-22
• [source] Xiaomi's MiMo v2.6 tops open-model index, RL run cost ~$3.5M and was livestreamed — Prompt Engineering · 2026-09-22
• Xiaomi MiMo-V2.6 details its largest RL scaling run: $2.6M, 1M-token contexts — KyeGomezB · 2026-09-22
• Xiaomi Open-Sources MiMo V2.6: Top Open-Source Model Matches Grok 4.7 at 1/30th the Cost — 新智元 · 2026-09-23
• Xiaomi's MiMo-V2.6 tech report: ~7k RL training data open-sourced, model shipped within a week of final RL run — rbhar90 · 2026-09-23
• Xiaomi's open-source MiMo V2.6 Pro hits 46 on AA index at $0.13/task, near GPT-5.6 Sol — LearnWithBishal · 2026-09-23
• Xiaomi Open-Sources MiMo-V2.6: 1.02T MoE Multimodal Agent Family Under MIT — burny_tech · 2026-09-23

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