# What a coding agent actually costs per month, by model (2026)

> Source: <https://dev.to/khavel/what-a-coding-agent-actually-costs-per-month-by-model-2026-3ac9>
> Published: 2026-07-16 11:44:07+00:00

"Which model should I run my coding agent on?" almost always turns into a price question once the first invoice lands. Coding agents are *token-hungry* — they read whole files, reason across a repo, and emit long diffs — so the model you pick shows up on your bill in a big way.

Here's the part nobody tells you: for a coding workload, **output price dominates**. An agent that burns ~90M input and ~25M output tokens a month pays for those 25M output tokens at rates that swing from $0.28 to $30 per million. That single number decides most of your bill.

Below is one fixed workload — **~90M input + ~25M output tokens/month** (a busy single-developer coding agent) — priced against each model's *current, official* API rates. Nothing here is invented; every figure is pulled live from [AI Model Watch](https://aimodelwatch.dev), which tracks these prices daily from provider pricing pages.

| Model | Input $/M | Output $/M | Est. monthly cost |
|---|---|---|---|
| Qwen3.5-Flash | $0.10 | $0.40 | $19 |
| DeepSeek-V4-Flash | $0.14 | $0.28 | $20 |
| Codestral (v25.08) | $0.30 | $0.90 | $50 |
| Gemini 3.1 Flash-Lite | $0.25 | $1.50 | $60 |
| DeepSeek-V4-Pro | $0.435 | $0.87 | $61 |
| Mistral Large 3 | $0.50 | $1.50 | $83 |
| Kimi K2.7 Code | $0.95 | $4.00 | $186 |
| Qwen3-Max | $1.20 | $6.00 | $258 |
| Grok 4.5 | $2.00 | $6.00 | $330 |
| Gemini 3.5 Flash | $1.50 | $9.00 | $360 |
| GPT-5.4 | $2.50 | $15.00 | $600 |
| GPT-5.6 Terra | $2.50 | $15.00 | $600 |
| Claude Sonnet 5 | $3.00 | $15.00 | $645 |
| Claude Opus 4.8 | $5.00 | $25.00 | $1,075 |
| GPT-5.6 Sol | $5.00 | $30.00 | $1,200 |

That's a **63× spread** — $19/mo to $1,200/mo — for the *same* number of tokens. The choice of model, not the amount of work, is what moves the bill an order of magnitude.

**1. Output tokens are where coding agents bleed.** Compare DeepSeek-V4-Flash ($0.28 out) to Claude Sonnet 5 ($15 out): a 54× output-price gap that a chat benchmark, which weights input heavily, would hide. Agents *write* a lot, so weight the output rate accordingly.

**2. "Cheap" and "specialist" aren't the same axis.** The two cheapest here are general-purpose small models (Qwen3.5-Flash, DeepSeek-V4-Flash), not the code-branded ones. Codestral and Kimi K2 Code are tuned for coding, but you pay for the tuning. Whether that tuning earns its 4–9× premium depends on your task — benchmark it on *your* repo, not on a leaderboard.

**3. The frontier tier is a different budget entirely.** Opus 4.8 and GPT-5.6 Sol land above $1,000/mo on this workload. They may well close the loop in fewer iterations — a frontier model that one-shots a task can be cheaper in practice than a cheap model that needs five tries. But that's an *efficiency* argument you have to verify, not assume.

The numbers above are current as of publication, but this corner of the market moves weekly: new coding models ship, prices get cut, and preview tiers graduate or get retired. If you're running an agent in production, a 2× output-price change is a real budget event.

AI Model Watch tracks every LLM's price, context window and deprecation status daily from official sources, and sends a **free email alert** the moment a model you rely on changes price or gets an end-of-life date. If you'd rather not re-check a pricing page every week: ** aimodelwatch.dev**.

*Full ranked coding-cost table and methodology: aimodelwatch.dev/guides/cheapest-llm-for-coding*