Cost per coding-agent request

Is Claude Fable 5.1 or Gemini 3.8 Flash cheaper for coding agents?

For coding agents, Claude Fable 5.1 costs 4.9x as much as Gemini 3.8 Flash per request ($0.24 vs $0.048 on our measured traffic), because Claude Fable 5.1 lists at $10 input, $0.25 cached input and $50 output per million tokens against $1.50, $0.15 and $7.50 for Gemini 3.8 Flash.

List prices: Anthropic pricing, Gemini API pricing, checked 2026-10-13. Request costs: Standard Compute gateway data, 79,301 coding-agent requests from 75 users, Sep 13 to Oct 12, 2026. How we compute this

Run any of these models in your agent from $19/month

See plans

Cost per coding-agent request, side by side

Cost at list price	Gemini 3.8 Flash	Fable 5.1
Prompt under 100K tokens50% of requests, 87% of input cached	$0.023	$0.12
Prompt of 100K to 272K39% of requests, 88% of input cached	$0.058	$0.28
Prompt over 272K tokens11% of requests, 86% of input cached	$0.13	$0.63
Average request	$0.048	$0.24
100 requests	$4.83	$23.76
Median session16 requests; a session ends after 10 idle minutes	$0.65	$3.26
A month of regular usemedian of 20 users active on 5+ days	$73.52	$332

Each logged request priced at the vendor’s list rates for its own token counts, including cache reads and any higher rate for long prompts. Average output: 698 tokens per request.

Benchmarks, speed and latency, side by side

Artificial Analysis	Gemini 3.8 Flash	Fable 5.1
Intelligence Index10 evaluations, 0 to 100	41	53
Terminal-Bench 4.0agentic coding in a terminal	19.7%	52.0%
Output speedmedian	145 tokens/s	71 tokens/s
Time to first answer tokenincludes thinking time	24 s	4.0 min

Source: Artificial Analysis (artificialanalysis.ai). Measured variants: Gemini 3.8 Flash (High), speed on Google; Claude Fable 5.1 (Max, Default Fallback), speed on Anthropic. Fetched October 13, 2026. Artificial Analysis runs Terminal-Bench 4.0 in its own setup, so its scores differ from the tbench.ai leaderboard.

What to watch for

Gemini 3.8 Flash figures use Google's standard price from January 1, 2027; until then Google charges half. Claude Fable 5.1 scores clearly higher on the benchmarks above, so it may finish hard tasks in fewer steps.

FAQ

Is Gemini 3.8 Flash cheaper than Claude Fable 5.1 for coding agents?

Yes, at list prices. 100 average coding-agent requests cost $4.83 on Gemini 3.8 Flash and $23.76 on Claude Fable 5.1. A median 16-request session costs $0.65 vs $3.26. Measured on 79,301 real coding-agent requests (Sep 13 to Oct 12, 2026).

How much does a month of Fable 5.1 vs Gemini 3.8 Flash cost?

For the median regular user in our data (1,478 requests in 30 days), about $332 on Claude Fable 5.1 and $73.52 on Gemini 3.8 Flash at list price. Heavier users pay proportionally more.

Claude Fable 5.1 vs Gemini 3.8 Flash: which is better for agents?

Claude Fable 5.1 scores higher on output quality (9.4/10 vs 7.9/10), while Gemini 3.8 Flash is the cheaper option. Claude Fable 5.1 is best for teams already standardized on Fable that want the newest premium Claude; Gemini 3.8 Flash is best for high-throughput agents and Gemini CLI users who want speed and big context. Live community votes on this page show what people actually prefer.

Can I switch between Claude Fable 5.1 and Gemini 3.8 Flash in the same agent?

Yes. Model-agnostic agents (Cline, Aider, OpenClaw, Hermes Agent, Kilo Code, OpenCode, Continue) let you swap models per task. Many people route hard tasks to the stronger model and routine work to the cheaper one.