Original Research

AI Model Release Timeline 2023–2026 — Every Major Model Launch

Comprehensive timeline of 45+ major AI model releases from GPT-4 to Llama 4. Every significant launch with parameters, context window, key capability, and open/closed status.

By Michael Lip · Updated April 2026

Methodology

Release dates are sourced from official provider announcements, blog posts, and GitHub release pages (queried via GitHub API on April 11, 2026 for meta-llama/llama-models, mistralai/mistral-inference, google/gemma, and deepseek-ai/DeepSeek-V3). Parameter counts are from official technical reports where available; estimated counts are marked with ~. Context windows from official documentation. "Open" means weights are publicly downloadable; "Closed" means API-only access.

Date Model Provider Parameters Context Open Key Capability
2023-02LLaMA 1 (7B-65B)Meta7B-65B2KYesFirst competitive open foundation model
2023-03GPT-4OpenAI~1.8T MoE8K/32KNoMultimodal, reasoning leap over GPT-3.5
2023-03Claude 1Anthropic~52B100KNo100K context window, Constitutional AI
2023-07Claude 2Anthropic~70B100KNoImproved coding and reasoning
2023-07Llama 2 (7B-70B)Meta7B-70B4KYesFirst commercial open-weights model
2023-09Mistral 7BMistral7B32KYesBest 7B model, Apache 2.0 license
2023-11GPT-4 TurboOpenAI~1.8T MoE128KNo128K context, 3x cheaper than GPT-4
2023-12Gemini 1.0 ProGoogle~50B32KNoGoogle's first Gemini model
2023-12Mixtral 8x7BMistral46.7B MoE32KYesFirst major open MoE model
2024-02Gemini 1.5 ProGoogle~300B MoE1MNo1 million token context window
2024-02Gemma 1 (2B/7B)Google2B/7B8KYesGoogle's first open model family
2024-03Claude 3 OpusAnthropic~200B200KNoNew frontier, matched GPT-4
2024-03Claude 3 SonnetAnthropic~70B200KNoBest mid-tier quality/cost ratio
2024-03Claude 3 HaikuAnthropic~20B200KNoFast, cheap, 200K context
2024-03DBRXDatabricks132B MoE32KYesEnterprise open MoE model
2024-04Llama 3 (8B/70B)Meta8B/70B8KYesSignificant quality jump, 15T training tokens
2024-04Phi-3 (mini/medium)Microsoft3.8B/14B4K/128KYesSmall model achieving GPT-3.5 quality
2024-05GPT-4oOpenAI~200B128KNoOmni: native audio, vision, text. 2x faster, 50% cheaper
2024-06Gemma 2 (9B/27B)Google9B/27B8KYesKnowledge distillation from larger models
2024-06Qwen 2 (0.5B-72B)Alibaba0.5B-72B128KYesMultilingual, strong coding performance
2024-07GPT-4o miniOpenAI~8B128KNo97% cheaper than GPT-4, replaces 3.5 Turbo
2024-07Llama 3.1 (8B-405B)Meta8B-405B128KYes405B: largest open model, tool use, 128K context
2024-07Mistral Large 2Mistral123B128KNoCompetitive frontier from European startup
2024-09o1-previewOpenAI~200B128KNoReasoning model: chain-of-thought at inference time
2024-09Qwen 2.5 (0.5B-72B)Alibaba0.5B-72B128KYesCoder variant, improved math and code
2024-10Claude 3.5 SonnetAnthropic~70B200KNoMatched Opus quality at Sonnet price
2024-11Grok-2xAI~300B MoE128KNoReal-time information access via X/Twitter
2024-12Llama 3.3 70BMeta70B128KYes405B quality distilled into 70B
2024-12DeepSeek V3DeepSeek671B MoE128KYesFrontier quality at $5.5M training cost
2024-12Phi-4Microsoft14B16KYesSTEM and reasoning focus, punches above weight
2025-01DeepSeek R1DeepSeek671B MoE128KYesOpen reasoning model matching o1
2025-01Codestral 25.01Mistral22B256KYesCode-specialized, 256K context
2025-02GPT-4.5OpenAI~1.8T128KNoLargest dense model, premium research tier
2025-03Gemini 2.5 ProGoogle~300B MoE1MNoThinking model with 1M context
2025-03Gemini 2.5 FlashGoogle~50B MoE1MNoFast + thinking mode, 1M context
2025-03Mistral Small 3.1Mistral24B128KYesVision + speed, $0.10/1M tokens
2025-04Llama 4 Scout/MaverickMeta17B-400B MoE10MYes10M context, native multimodality
2025-04o3OpenAI~200B200KNoAdvanced reasoning, tool use, 200K context
2025-04o4-miniOpenAI~8B200KNoBudget reasoning model
2025-04Qwen 3 (0.6B-235B)Alibaba0.6B-235B128KYesThinking + non-thinking modes, MoE
2025-06Claude Opus 4.6Anthropic~300B200KNoBest coding model, extended thinking, agents
2025-06Claude Sonnet 4Anthropic~70B200KNoNear-Opus quality at Sonnet price
2025-10Claude Haiku 3.5Anthropic~20B200KNoFast, cheap, 200K context

Parameter counts with ~ are estimated. MoE = Mixture of Experts (active parameters are lower than total). Context shown in tokens unless otherwise noted.

Frequently Asked Questions

How many major AI models were released in 2024?

2024 saw approximately 25 major model releases, making it the most prolific year. Key releases included GPT-4o and GPT-4o mini (OpenAI), Claude 3 family and Claude 3.5 Sonnet (Anthropic), Gemini 1.5 Pro and Flash (Google), Llama 3 and 3.1 (Meta), Mistral Large and Codestral (Mistral), and DeepSeek V3. Multiple frontier models launched each quarter.

What was the most significant AI model release?

Several were transformative: GPT-4 (March 2023) proved multimodal AI was viable; Llama 2 (July 2023) democratized open models; GPT-4o (May 2024) brought frontier quality at 6x lower cost; DeepSeek V3 (December 2024) showed frontier quality at dramatically lower training cost; o1 (September 2024) introduced reasoning-time compute scaling.

Are open-source models catching up to proprietary ones?

Yes, significantly. In early 2023, GPT-4 led open models by 15-20% on benchmarks. By late 2024, Llama 3.1 405B and DeepSeek V3 matched GPT-4 Turbo. DeepSeek R1 matched o1 on reasoning. The remaining gap is primarily in the largest frontier models (GPT-4.5, Claude Opus 4.6) which maintain a 3-5% edge on the hardest benchmarks.

What is the trend in AI model sizes?

Sizes scaled up through 2023, then shifted toward efficiency in 2024-2025. MoE became dominant: DeepSeek V3 (671B total, ~37B active) achieves high quality with lower inference costs. Small models also improved: Phi-4 (14B) and Mistral Small 3.1 (24B) match 2023-era 70B models on many tasks.

Which company has released the most AI models?

Meta leads in volume with the Llama series across multiple variants. Google follows with Gemini/Gemma. OpenAI has fewer but more impactful releases. Alibaba's Qwen team has been prolific with Qwen 2/2.5/3. Mistral released the most models relative to company size.