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Claude Opus 4.8 vs Claude Sonnet 5

Claude Opus 4.8 and Claude Sonnet 5 are closely matched at 51.7 and 49.3 on the LLM Stats Score. Claude Sonnet 5 is 2.5x cheaper per token.

Anthropic · Anthropic · Updated for 2026

Which is better?

Claude Opus 4.8 and Claude Sonnet 5 are closely matched on the overall LLM Stats Score at 51.7 and 49.3.

In the 14 individual benchmarks reported for both models, Claude Opus 4.8 wins 11; this is a narrower head-to-head signal than the composite indexes.

On price, Claude Sonnet 5 is roughly 2.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Opus 4.8

  • you value its reported benchmark strengths — it wins 11 of 14 exact shared results

Choose Claude Sonnet 5

  • cost matters — it's about 2.5x cheaper per token
  • you want the most recent training data — it shipped Jun 2026

At a glance

The differences that matter most.

Core performance indexes
51.7
#10
49.3
#15
51.2
#10
48.8
#16
43.8
#8
39.8
#14
36.8
#14
33.7
#19
Cost, coverage & limits
Benchmark wins
11 of 14
3 of 14
Input price
$5.00 / M
$2.00 / M
Output price
$25.00 / M
$10.00 / M
Context window
1,000,000
1,000,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Claude Opus 4.8
Claude Sonnet 5
39.5#18
36.5#36
37.2#6
34.4#12
31.1#11
25.6#27
36.4#7
32.6#17
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

26 reported for Claude Opus 4.8 · 22 for Claude Sonnet 5

14 shared

Claude Opus 4.8 outperforms in 11 benchmarks (CharXiv-R, DeepSWE 1.1, FrontierCode 1.1, Humanity's Last Exam, OfficeQA Pro, OSWorld-Verified, SWE-bench Multilingual, SWE-Bench Multimodal, SWE-Bench Pro, SWE-Bench Verified, Toolathlon), while Claude Sonnet 5 is better at 3 benchmarks (BrowseComp, HealthBench Professional, Terminal-Bench 2.0).

Claude Opus 4.8 significantly outperforms across most benchmarks.

Fri Aug 28 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Claude Sonnet 5 costs less

For input processing, Claude Opus 4.8 ($5.00/1M tokens) is 2.5x more expensive than Claude Sonnet 5 ($2.00/1M tokens).

For output processing, Claude Opus 4.8 ($25.00/1M tokens) is 2.5x more expensive than Claude Sonnet 5 ($10.00/1M tokens).

In conclusion, Claude Opus 4.8 is more expensive than Claude Sonnet 5.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Aug 28 2026 • llm-stats.com
Anthropic
Claude Opus 4.8
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
Anthropic
Claude Sonnet 5
Input tokens$2.00
Output tokens$10.00
Best providerAnthropic
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

Both models have the same input context window of 1,000,000 tokens. Claude Opus 4.8 can generate longer responses up to 128,000 tokens, while Claude Sonnet 5 is limited to 64,000 tokens.

Anthropic
Claude Opus 4.8
Input1,000,000 tokens
Output128,000 tokens
Anthropic
Claude Sonnet 5
Input1,000,000 tokens
Output64,000 tokens
Fri Aug 28 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Opus 4.8 and Claude Sonnet 5 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Opus 4.8

Text
Images
Audio
Video

Claude Sonnet 5

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Opus 4.8

Proprietary

Closed source

Claude Sonnet 5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4.8 was released on 2026-05-28, while Claude Sonnet 5 was released on 2026-06-30.

Claude Sonnet 5 is 1 month newer than Claude Opus 4.8.

Claude Opus 4.8

May 28, 2026

3 months ago

Claude Sonnet 5

Jun 30, 2026

1 months ago

1mo newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Claude Opus 4.8 is available from Anthropic, Vertex AI. Claude Sonnet 5 is available from Anthropic.

Claude Opus 4.8

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M
vertex logo
Unknown Organization
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M

Claude Sonnet 5

anthropic logo
Anthropic
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Claude Opus 4.8 and Claude Sonnet 5 side-by-side, then vote on the output you prefer.

Claude Opus 4.8
✓ Preferred
Claude Sonnet 5
Open in Playground

FAQ

Common questions about Claude Opus 4.8 vs Claude Sonnet 5.

Which is better, Claude Opus 4.8 or Claude Sonnet 5?

Claude Opus 4.8 and Claude Sonnet 5 are closely matched on the LLM Stats Score at 51.7 and 49.3. Claude Opus 4.8 is made by Anthropic and Claude Sonnet 5 is made by Anthropic. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Opus 4.8 compare to Claude Sonnet 5 in benchmarks?

Claude Opus 4.8 scores GPQA: 93.6%, DeepSearchQA: 93.1%, CharXiv-R: 89.9%, SWE-Bench Verified: 88.6%, ScreenSpot Pro: 87.9%. Claude Sonnet 5 scores CharXiv-R: 88.3%, ChartMuseum: 86.7%, SWE-Bench Verified: 85.2%, BrowseComp: 84.7%, GDP.pdf: 81.6%.

Is Claude Opus 4.8 cheaper than Claude Sonnet 5?

Claude Sonnet 5 is 2.5x cheaper for input tokens. Claude Opus 4.8 costs $5.00/M input and $25.00/M output via anthropic. Claude Sonnet 5 costs $2.00/M input and $10.00/M output via anthropic.

What are the context window sizes for Claude Opus 4.8 and Claude Sonnet 5?

Claude Opus 4.8 supports 1.0M tokens and Claude Sonnet 5 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Opus 4.8 and Claude Sonnet 5?

Key differences include LLM Stats Score (51.7 vs 49.3), input pricing ($5.00 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.