LLM Cost Calculator

OpenAI API Pricing 2026

The most widely-used LLM API. GPT-5.5 and GPT-5.4 are the current frontier tiers; o3-pro and o4-mini lead the reasoning tier. OSS 120B offers open-source quality at near-free pricing.

Pricing verified 2026-06-06. Sourced from platform.openai.com.

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OpenAI Model Pricing

Prices in USD per 1M tokens

ModelInput / 1MOutput / 1MContext
GPT-5.5
Latest OpenAI frontier model; 272K context standard tier
$5$30272,000
GPT-5.5 Pro
GPT-5.5 Pro; 1M context; max capability tier
$30$1801,050,000
GPT-5.4
Strong coding & professional workloads; 272K context standard tier
$2.5$15272,000
GPT-5.4 Mini
Best mini model for coding, computer use, and subagents
$0.75$4.5272,000
GPT-5.4 Nano
Ultra-low-cost GPT-5.4 tier for classification and routing
$0.2$1.25272,000
GPT-5.4 Pro
GPT-5.4 Pro; 1M context; enterprise workloads
$30$1801,050,000
GPT-5 Pro
GPT-5 Pro; 400K context; heavy inference
$15$120400,000
o3 Deep Research
o3 with deep-research mode; extended reasoning budget
$10$40200,000
o4 Mini Deep Research
o4-mini deep-research; cost-effective research tasks
$2$8200,000
GPT-5 Codex
GPT-5 Codex; 400K context; coding-optimized
$1.25$10400,000
GPT-5 Mini
Previous-gen budget model; GPT-5.4 Mini is the current mini tier
$0.25$2128,000
GPT-5
Previous flagship; use GPT-5.5 for new projects
$1.25$10128,000
GPT-5 Nano
GPT-5 Nano; 400K context; ultra-cheap classification & routing
$0.05$0.4400,000
gpt-oss-120b
OpenAI open-source 120B; runs on Groq/Together at low cost
$0.04$0.18131,072
o3 Pro
o3 Pro; extended thinking compute; top-tier reasoning
$20$80200,000
GPT-4.1
Previous production tier with 1M context; superseded by GPT-5.4
$2$81,000,000
GPT-4.1 Mini
Previous mid-tier; 1M context window
$0.4$1.61,000,000
GPT-4.1 Nano
Previous budget tier; GPT-5.4 Nano is cheaper for new workloads
$0.1$0.41,000,000
o3
Flagship reasoning; use when o4-mini accuracy is insufficient
$2$8200,000
o4-mini
Best-value reasoning model; chain-of-thought built in
$1.1$4.4200,000
o1-pro
Auto-added 2026-06
$150$600200,000
o3 Mini
Auto-added 2026-06
$1.1$4.4200,000
o1
Auto-added 2026-06
$15$60200,000
GPT-4o-mini
Auto-added 2026-06
$0.15$0.6128,000

Estimated Monthly Cost (70% input / 30% output split)

Model1M tokens/mo10M tokens/mo100M tokens/mo1B tokens/mo
GPT-5.5$12.50$125$1,250$12,500
GPT-5.5 Pro$75.00$750$7,500$75,000
GPT-5.4$6.25$62.50$625$6,250
GPT-5.4 Mini$1.87$18.75$188$1,875
GPT-5.4 Nano$0.515$5.15$51.50$515
GPT-5.4 Pro$75.00$750$7,500$75,000
GPT-5 Pro$46.50$465$4,650$46,500
o3 Deep Research$19.00$190$1,900$19,000
o4 Mini Deep Research$3.80$38.00$380$3,800
GPT-5 Codex$3.88$38.75$388$3,875
GPT-5 Mini$0.775$7.75$77.50$775
GPT-5$3.88$38.75$388$3,875
GPT-5 Nano$0.155$1.55$15.50$155
gpt-oss-120b$0.082$0.820$8.20$82.00
o3 Pro$38.00$380$3,800$38,000
GPT-4.1$3.80$38.00$380$3,800
GPT-4.1 Mini$0.760$7.60$76.00$760
GPT-4.1 Nano$0.190$1.90$19.00$190
o3$3.80$38.00$380$3,800
o4-mini$2.09$20.90$209$2,090
o1-pro$285$2,850$28,500$285,000
o3 Mini$2.09$20.90$209$2,090
o1$28.50$285$2,850$28,500
GPT-4o-mini$0.285$2.85$28.50$285

Frequently Asked Questions

How much does OpenAI LLM API cost?

OpenAI offers 24 models ranging from $0.040/1M to $150.00/1M input tokens. The most widely-used LLM API. GPT-5.5 and GPT-5.4 are the current frontier tiers; o3-pro and o4-mini lead the reasoning tier. OSS 120B offers open-source quality at near-free pricing.

Is OpenAI cheaper than self-hosting?

For low-volume workloads (under 100M tokens/month), cloud APIs like OpenAI are almost always cheaper than purchasing and maintaining GPU hardware. Use our calculator to find the exact break-even point for your usage.