Cheapest LLM API right now (2026-10-15)

Every tracked model ranked by real monthly cost for a typical chatbot workload, with price sources and cross-checks.

Bottom line: cheapest is Meta: Llama 3.1 8B Instruct at about $16.76/month; the median model costs $287.88; the most expensive, Anthropic: Claude Fable 5, costs $5,386. That is a 321× spread for the same workload.

Scenario: 10,000 monthly users × 30 messages, 600 words in / 150 words out per message.

VendorModelIn $/1MOut $/1MEst. monthly costSource / check
Meta (Llama)Meta: Llama 3.1 8B Instruct$0.05$0.08$16.76source 2026-10-15 ✔ matches
Meta (Llama)Meta: Llama 3.2 1B Instruct$0.027$0.201$18.49source 2026-10-15 ✔ matches
MistralMistral: Ministral 3 3B 2512$0.1$0.1$29.93source 2026-10-15 ✔ matches
Meta (Llama)Meta: Llama 3.2 3B Instruct$0.05$0.33$31.72source 2026-10-15 ✔ matches
DeepSeekDeepSeek: DeepSeek V4 Flash 0423$0.091$0.182$32.68source 2026-10-15 ℹ vs market median ($0.14/$0.28)
DeepSeekDeepSeek: DeepSeek V4 Flash 0731$0.0051$0.64$39.52source 2026-10-15 ℹ vs market median ($0.14/$0.4245)
MistralMistral: Ministral 3 8B 2512$0.15$0.15$44.89source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Haiku 5.5$0.1$0.5$53.87source 2026-10-15 ✔ matches
OpenAIOpenAI: GPT-6 Luna Pro$0.1$0.5$53.87source 2026-10-15 ✔ matches
OpenAIOpenAI: GPT-6 Luna$0.1$0.5$53.87source 2026-10-15 ✔ matches
Meta (Llama)Meta: Llama Guard 4 12B$0.18$0.18$53.87source 2026-10-15 ✔ matches
MistralMistral: Ministral 3 14B 2512$0.2$0.2$59.85source 2026-10-15 ✔ matches
DeepSeekDeepSeek: DeepSeek V4.1 Flash$0.15$0.6$71.82source 2026-10-15 ✔ matches
MistralMistral: Mistral Small 4$0.15$0.6$71.82source 2026-10-15 ✔ matches
Meta (Llama)Meta: Llama 4 Scout$0.18$0.59$78.40source 2026-10-15 ℹ vs market median ($0.1/$0.3139)
Meta (Llama)Meta: Llama 4 Maverick$0.1875$0.6525$83.94source 2026-10-15 ℹ vs market median ($0.2546/$0.85)
DeepSeekDeepSeek: DeepSeek V3.2 Exp$0.27$0.41$89.18source 2026-10-15 ⚠ differs from lab price ($0.28/$0.42)
DeepSeekDeepSeek: DeepSeek V4 Flash Vision Exp$0.2156$0.6468$90.33source 2026-10-15 ℹ vs market median ($0.2242/$0.6725)
DeepSeekDeepSeek: DeepSeek V3.2$0.259$0.8$109.88source 2026-10-15 ⚠ differs from lab price ($0.28/$0.42)
Meta (Llama)Meta: Llama 3.1 70B Instruct$0.4$0.4$119.70source 2026-10-15 ℹ vs market median ($0.4/$0.56)
DeepSeekDeepSeek: DeepSeek V4 Pro 0423$0.3583$0.7165$128.66source 2026-10-15 ⚠ differs from lab price ($0.66/$1.98)
GoogleGoogle: Gemini 3.1 Flash Lite$0.25$1.5$149.62source 2026-10-15 ✔ matches
Meta (Llama)Meta: Llama 3.3 70B Instruct$0.59$0.79$188.53source 2026-10-15 ℹ vs market median ($0.5683/$0.72)
MistralMistral: Mistral Large 3 2512$0.5$1.5$209.47source 2026-10-15 ✔ matches
MistralMistral: Devstral 2 2512$0.4$2.0$215.46source 2026-10-15 ✔ matches
GoogleGoogle: Gemini 3.5 Flash Lite$0.3$2.5$221.44source 2026-10-15 ✔ matches
DeepSeekDeepSeek: DeepSeek V4 Pro 0813$0.66$1.98$276.51source 2026-10-15 ✔ matches
MistralMistral: Mistral Large 4$0.68$2.09$287.88source 2026-10-15 ✔ matches
xAISpaceXAI: Grok Build 0.1$1.0$2.0$359.10source 2026-10-15 ✔ matches
GoogleGoogle: Gemini 3.7 Flash$0.75$3.75$403.99source 2026-10-15 ✔ matches
GoogleGoogle: Gemini 3.6 Flash$0.75$3.75$403.99source 2026-10-15 ✔ matches
GoogleGoogle: Gemini 3.8 Flash$0.825$4.125$444.39source 2026-10-15 ⚠ differs from lab price ($0.75/$3.75)
xAISpaceXAI: Grok 4.3$1.25$2.5$448.88source 2026-10-15 ✔ matches
xAISpaceXAI: Grok 4.20 Multi-Agent$1.25$2.5$448.88source 2026-10-15 ✔ matches
xAISpaceXAI: Grok 4.20$1.25$2.5$448.88source 2026-10-15 ✔ matches
GoogleGoogle: Nano Banana 2.1$1.5$7.5$807.98source 2026-10-15 no 2nd source
MistralMistral: Mistral Medium 3.5$1.5$7.5$807.98source 2026-10-15 ✔ matches
xAISpaceXAI: Grok 4.7$2.0$6.0$837.90source 2026-10-15 ✔ matches
xAISpaceXAI: Grok 4.6$2.0$6.0$837.90source 2026-10-15 ✔ matches
xAISpaceXAI: Grok 4.5$2.0$6.0$837.90source 2026-10-15 ✔ matches
GoogleGoogle: Gemini 3.5 Flash$1.5$9.0$897.75source 2026-10-15 ✔ matches
GoogleGoogle: Gemini 4 Argon$2.0$10.0$1,077source 2026-10-15 no 2nd source
OpenAIOpenAI: GPT-6.1 Sol Pro$2.0$10.0$1,077source 2026-10-15 ✔ matches
OpenAIOpenAI: GPT-6.1 Sol$2.0$10.0$1,077source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Sonnet 5.5$2.0$10.0$1,077source 2026-10-15 ✔ matches
OpenAIOpenAI: GPT-6 Sol Pro$2.0$10.0$1,077source 2026-10-15 ✔ matches
OpenAIOpenAI: GPT-6 Sol$2.0$10.0$1,077source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Sonnet 5$2.0$10.0$1,077source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Opus 5.5$4.0$20.0$2,155source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Opus 5$5.0$25.0$2,693source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Opus 4.8$5.0$25.0$2,693source 2026-10-15 ✔ matches
OpenAIOpenAI: GPT-6 Astra$10.0$50.0$5,386source 2026-10-15 ✔ matches
OpenAIOpenAI: GPT-6 Astra Pro$10.0$50.0$5,386source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Fable 5.1$10.0$50.0$5,386source 2026-10-15 ✔ matches
AnthropicAnthropic: Claude Fable 5$10.0$50.0$5,386source 2026-10-15 ✔ matches

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