Quick Answer
DeepSeek V4 Flash vs Grok 4.5: Cheapest Coding Agent Aug 2026
The Short Answer
For the cheapest coding agent in August 2026: DeepSeek V4 Flash 0731 wins on raw cost at $0.14/$0.28 per MTok with a 1M context. Grok 4.5 ($2/$6) costs far more but delivers stronger agentic reasoning and Cursor-native behavior.
The Comparison
| DeepSeek V4 Flash 0731 | Grok 4.5 | |
|---|---|---|
| API price (per MTok) | $0.14 / $0.28* | $2 / $6 |
| Context | 1M | 500K |
| Params | 284B MoE (13B active) | 1.5T (V9 foundation) |
| Released | Jul 31, 2026 | Jul 8, 2026 |
| Best at | Cheapest high-volume agent | Frontier-adjacent value agent |
*Max-effort reasoning; blended rate ~$0.06/MTok. Grok doubles over 200K input tokens.
Where Each Wins
- DeepSeek V4 Flash 0731 → cheapest by far. 284B MoE with 13B active, 1M context, and DSpark-style efficiency. Ranks #29 of 160 for coding across trackers. At $0.14/$0.28 it’s ~20-30x cheaper on output than Grok 4.5.
- Grok 4.5 → value with frontier quality. Trained on real Cursor developer sessions, on par with GPT-5.5 in Codex at ~half the per-task cost, and available in Cursor, Grok Build, and GitHub Copilot.
Cost Reality
At high volume, DeepSeek’s pricing is transformative — a full agentic loop that costs dollars on Grok can cost cents on DeepSeek. Grok’s premium buys tighter agentic behavior and IDE integration. If your agent runs thousands of tool calls a day, DeepSeek’s per-token gap compounds fast.
Verdict
- Cheapest capable agent → DeepSeek V4 Flash 0731
- Best value with frontier-adjacent quality → Grok 4.5
- High-volume automation → DeepSeek V4 Flash 0731
Sources
- DeepSeek API pricing: api-docs.deepseek.com/quick_start/pricing
- xAI — Grok 4.5: x.ai/news/grok-4-5