Cheaper alternatives to Claude Sonnet 4.5

Anthropic LMArena 1438 $6.00/M on a balanced workload prices as of 2026-08-28

11 models are both better and cheaper, giving up nothing.

Of the 133 models carrying both an independent score and a published price at the same delivery mode, 32 score at least as high as Claude Sonnet 4.5 and cost no more under at least one workload. 30 of them are genuinely cheaper; the rest match the price and win on score alone. 11 match or beat it on every capability we hold — context, maximum output, input modes, tool use and extended reasoning. 21 do not, and every row names what it drops.

Dominance is not a property of a model. It is a property of a model, a capability lens and a workload, and all three are named on every row. Scores are LMArena Elo, used under CC BY 4.0 from the official dataset; prices are blended per million tokens. A higher score is not a drop-in replacement.

This page is built from that comparison and nothing else. When no model is both better and cheaper than Claude Sonnet 4.5, it is not generated.

Where it holds

Workload	Claude Sonnet 4.5 $/M	Better and cheaper	With a trade
Balanced	$6.00	11	21
Summarise	$2.83	11	21
Chat	$6.99	11	21
Code gen	$9.98	11	21
Agentic	$3.19	11	21

Workload mixes are defined on the methodology page. Cached input is priced at the cached rate, and reasoning tokens at the worse of the reasoning and output rates.

What you would be replacing

Intelligence	1438
Context window	1M
Max output	64K
Input modes	text, image, file
Tool use	yes
Extended reasoning	yes

A replacement has to clear every line above, not just the score. Full record for Claude Sonnet 4.5.

Better and cheaper, nothing given up 11

Each of these matches or beats Claude Sonnet 4.5 on context, maximum output, input modes, tool use and reasoning, scores at least as high, and costs no more.

#	Model	Intelligence	$/M	Holds under
1	Gemini 3.7 Flash Google	1490.2 +52.2	$0.750	Balanced −88% Summarise −88% Chat −87% Code gen −88% Agentic −87%
2	Gemini 3.5 Flash Google	1482.6 +44.6	$3.38	Balanced −44% Summarise −47% Chat −41% Code gen −41% Agentic −43%
3	Muse Spark 1.1 Meta	1478.3 +40.3	$2.00	Balanced −67% Summarise −62% Chat −70% Code gen −70% Agentic −67%
4	Gemini 3.6 Flash Google	1476.5 +38.5	$1.50	Balanced −75% Summarise −75% Chat −75% Code gen −75% Agentic −75%
5	Gemini 3.1 Pro Preview Google	1479.5 +41.5	$4.50	Balanced −25% Summarise −30% Chat −22% Code gen −21% Agentic −24%
6	GPT-5.4 OpenAI	1469.6 +31.6	$5.63	Balanced −6% Summarise −12% Chat −2% Code gen −2% Agentic −5%
7	Gemini 2.5 Pro Google	1457.3 +19.3	$3.44	Balanced −43% Summarise −52% Chat −37% Code gen −36% Agentic −41%
8	Claude Sonnet 4.6 Anthropic	1457.6 +19.6	$6.00	Balanced same price Summarise same price Chat same price Code gen same price Agentic same price
9	GPT-5.6 Sol OpenAI	1454.2 +16.2	$4.00	Balanced −33% Summarise −33% Chat −33% Code gen −33% Agentic −33%
10	GPT-5.6 Terra OpenAI	1446 tie	$4.50	Balanced −25% Summarise −30% Chat −22% Code gen −21% Agentic −24%
11	Claude Sonnet 5 Anthropic	1442.3 tie	$4.00	Balanced −33% Summarise −33% Chat −33% Code gen −33% Agentic −33%

Cheaper and higher-scoring, but you give something up 21

These score at least as high and cost no more on the two plotted axes, and lose something that is not on them. Read the last column before switching.

Model	Intelligence	$/M	Holds under	What you give up
Qwen3.8 Max Qwen	1481.9 +43.9	$3.00	Balanced −50% Summarise −40% Chat −56% Code gen −57% Agentic −51%	no file input
GLM 5.3 Z.ai	1476.9 +38.9	$2.15	Balanced −64% Summarise −57% Chat −68% Code gen −69% Agentic −63%	no image, file input
Kimi K3 Moonshot AI	1476.3 +38.3	$6.00	Balanced same price Summarise same price Chat same price Code gen same price Agentic same price	no file input
MiMo-V2.5-Pro Xiaomi	1465 +27	$0.544	Balanced −91% Summarise −88% Chat −93% Code gen −93% Agentic −92%	no image, file input
GLM 5.2 Z.ai	1465.4 +27.4	$1.83	Balanced −70% Summarise −63% Chat −73% Code gen −74% Agentic −69%	no image, file input
GLM 5.1 Z.ai	1464.1 +26.1	$1.94	Balanced −68% Summarise −61% Chat −71% Code gen −72% Agentic −67%	1.0M → 205K context no image, file input
Qwen3.7 Plus Qwen	1456.2 +18.2	$0.560	Balanced −91% Summarise −90% Chat −91% Code gen −91% Agentic −90%	no file input
Kimi K2.6 Moonshot AI	1455 +17	$1.71	Balanced −71% Summarise −69% Chat −72% Code gen −73% Agentic −71%	1.0M → 262K context no file input
Grok 4.5 xAI	1452.3 +14.3	$3.00	Balanced −50% Summarise −39% Chat −56% Code gen −57% Agentic −50%	1.0M → 500K context
Kimi K2.5 Moonshot AI	1445.2 tie	$0.900	Balanced −85% Summarise −85% Chat −85% Code gen −85% Agentic −85%	1.0M → 262K context no file input
GLM 5 Z.ai	1445.2 tie	$0.930	Balanced −85% Summarise −81% Chat −86% Code gen −86% Agentic −84%	1.0M → 205K context no image, file input
Qwen3.6 Max Preview Qwen	1446.3 tie	$2.31	Balanced −61% Summarise −55% Chat −56% Code gen −59% Agentic −44%	1.0M → 262K context no image, file input
Gemma 4 31B Google	1441.7 tie	$0.152	Balanced −97% Summarise −97% Chat −97% Code gen −98% Agentic −97%	1.0M → 262K context 64K → 16K max output no file input
Hy3 Tencent	1441.2 tie	$0.144	Balanced −98% Summarise −97% Chat −98% Code gen −98% Agentic −97%	1.0M → 262K context no image, file input
Qwen3.8 27B Qwen	1440.8 tie	$0.956	Balanced −84% Summarise −85% Chat −83% Code gen −83% Agentic −83%	no file input
Grok 4.6 xAI	1443.7 tie	$3.00	Balanced −50% Summarise −37% Chat −55% Code gen −57% Agentic −47%	1.0M → 500K context
GLM 4.6 Z.ai	1439.8 tie	$0.875	Balanced −85% Summarise −84% Chat −86% Code gen −86% Agentic −85%	1.0M → 205K context no image, file input
DeepSeek V4 Pro 0423 DeepSeek	1439.2 tie	$1.09	Balanced −82% Summarise −76% Chat −86% Code gen −87% Agentic −84%	no image, file input
Qwen3.5 397B A17B Qwen	1438.3 tie	$0.877	Balanced −85% Summarise −83% Chat −83% Code gen −84% Agentic −79%	1.0M → 262K context no file input
Inkling Thinking Machines	1439.2 tie	$1.73	Balanced −71% Summarise −69% Chat −72% Code gen −72% Agentic −70%	no file input
GPT-5.1 OpenAI	1441.4 tie	$3.44	Balanced −43% Summarise −52% Chat −37% Code gen −36% Agentic −41%	1.0M → 400K context

What this compares, and what it leaves out

Quality is LMArena Elo, used under CC BY 4.0 from the official dataset. The 95% confidence interval on a difference between two scores is about ±10.68 points, so a gap smaller than that is marked tie rather than an improvement — see significance bands.
188 further models at this delivery mode carry a price but no independent score. They are absent from the comparison in both directions — unrated is not a zero, and an unmeasured model is neither an alternative nor a worse buy.
Retired models are never offered as an alternative, and a model only competes against its own delivery mode: batch trades latency for price, so it is not a like-for-like swap.
Nothing here measures latency, throughput, rate limits or how a model behaves on your prompts. Two models with the same index score are not interchangeable.
The models that nothing beats on both axes are on the value frontier, and every other model something cheaper beats is listed here.