Best Cheap AI API 2026: Price Per Token, Ranked
The Short Answer
As of August 2026, the cheapest capable flagship-family API is DeepSeek V4 Flash at $0.14/$0.28 per MTok (off-peak). For frontier quality on a budget, Grok 4.5 and Qwen3.8-Max tie at $2/$6 — ~2.5x cheaper than GPT-5.6 Sol or Claude Opus 5.
Cheapest Capable APIs (Ranked)
| Model | Input | Output | Notes |
|---|---|---|---|
| DeepSeek V4 Flash | $0.14 | $0.28 | Off-peak; 2x peak; best cheap-but-capable |
| GPT-5.6 Luna | $0.20 | $1.20 | After 80% cut (Jul 30); free ChatGPT default |
| Gemini 3.5 Flash-Lite | $0.30 | $2.50 | Google-native, cheap multimodal |
| DeepSeek V4 Pro | ~$0.44 | ~$0.87 | Off-peak; frontier-class open model |
| Gemini 3.6 Flash | $1.50 | $7.50 | New Google default; 65% fewer output tokens |
Cheapest Frontier Tier
| Model | Input | Output | Why |
|---|---|---|---|
| Grok 4.5 / 4.6 | $2 | $6 | Cheapest frontier; high token efficiency |
| Qwen3.8-Max | $2 | $6 | Matches Grok; open weights (week of Aug 10) |
| GPT-5.6 Terra | $2 | $12 | Cut 20% Jul 30; solid mid-tier |
Ultra-Cheap (Lower Capability)
Rate-bottom options like Qwen3.7 Flash hit $0.03/$0.13 per MTok — great for classification, extraction, and high-volume light tasks, but not for hard reasoning or agentic coding.
Cost Per Task
For a 30K-in/5K-out task: Luna ~$0.06, Grok 4.5 ~$0.09, Gemini 3.6 Flash ~$0.08, DeepSeek V4 Pro (off-peak) ~$0.017. Formula: 30 × (in ÷ 1000) + 5 × (out ÷ 1000).
Which Should You Pick?
- Best cheap + capable → DeepSeek V4 Flash.
- Cheapest frontier quality → Grok 4.5/4.6 or Qwen3.8-Max.
- Google-native cheap → Gemini 3.6 Flash / 3.5 Flash-Lite.
- Rock-bottom light tasks → Qwen3.7 Flash.
The Reality Check
Watch peak/valley pricing — DeepSeek rates double during peak (1–4 & 6–10 UTC), so batch off-peak. And cheap tokens on a weak model can cost more per successful task if you burn retries. Match model capability to task difficulty, then optimize price.
Sources
- AIpricing.guru — cheapest flagship API (DeepSeek V4 Flash $0.14): aipricing.guru
- BenchLM — LLM API pricing calculator (Aug 2026): benchlm.ai
- DeepSeek — official API pricing: api-docs.deepseek.com