What is the cheapest coding-agent model in August 2026?

DeepSeek V4 Flash 0731 is the cheapest at $0.14 input / $0.28 output per million tokens off-peak (~$0.0056 per 30K-in/5K-out task). Grok 4.5 costs $2/$6 (~$0.09/task) and Gemini 3.6 Flash costs $1.50/$7.50 (~$0.0825/task). DeepSeek is roughly 15x cheaper per task than the other two.

Is Grok 4.5 or Gemini 3.6 Flash better for coding agents?

Grok 4.5 is stronger on agentic benchmarks — 83.3% on Terminal-Bench 2.1 and roughly 2x token efficiency (fewer steps per task), which narrows its real cost gap. Gemini 3.6 Flash became Google's default in July 2026 and uses up to 65% fewer output tokens than 3.5 Flash, making it efficient and reliable for high-volume multimodal work.

Which cheap model should I use for high-volume coding?

For pure cost, DeepSeek V4 Flash 0731. For the best balance of price and agentic quality, Grok 4.5's step-efficiency often makes it competitive despite the higher per-token rate. Use Gemini 3.6 Flash when you need Google-ecosystem multimodal input at low output cost.

Quick Answer

DeepSeek V4 Flash vs Grok 4.5 vs Gemini 3.6 Flash: Cheapest Coding Agent (August 2026)

Published: August 1, 2026

The Short Answer

For the cheapest coding agent in August 2026, DeepSeek V4 Flash 0731 wins on raw price (~$0.0056/task). But Grok 4.5 is the strongest agent of the three (83.3% Terminal-Bench 2.1, ~2× step efficiency), and Gemini 3.6 Flash is the efficient multimodal default. Cost order: DeepSeek ≪ Gemini ≈ Grok.

The Comparison

	DeepSeek V4 Flash 0731	Grok 4.5	Gemini 3.6 Flash
Price (per MTok)	$0.14 / $0.28	$2 / $6	$1.50 / $7.50
Cost per task*	~$0.0056	~$0.09	~$0.0825
Context	1M	500K	1M
Terminal-Bench 2.1	82.7	83.3	—
Efficiency edge	Cheapest tokens	~2x fewer steps	~65% fewer output tokens
Released	Jul 31, 2026	Jul 8, 2026	Jul 21, 2026

*30K in / 5K out; DeepSeek off-peak (2x during peak).

Where Each Wins

DeepSeek V4 Flash 0731 → raw cost. ~15× cheaper per task than the others. Native Codex + Responses API support and DSpark speculative decoding make it a legit drop-in for Cursor, Claude Code, and OpenCode.
Grok 4.5 → best agent quality per dollar. Its ~2× token efficiency (solving tasks in under half the steps) means the $2/$6 rate buys fewer total tokens, so real jobs often cost less than the sticker price implies. Trained on trillions of Cursor tokens.
Gemini 3.6 Flash → efficient multimodal default. Google’s July 2026 default uses up to 65% fewer output tokens than 3.5 Flash, keeping the pricier $7.50 output rate in check for high-volume work.

Verdict

Cheapest possible → DeepSeek V4 Flash 0731
Best agent per dollar → Grok 4.5
Multimodal + Google stack → Gemini 3.6 Flash

Sources

DeepSeek API pricing: api-docs.deepseek.com/quick_start/pricing
xAI — Grok 4.5: x.ai/news/grok-4-5