Claude Sonnet 5 Rumored at Half the Price of Opus 4.5

Sonnet 5 Pricing Leak: 50% Cheaper Than Opus?

Multiple industry sources suggest Claude Sonnet 5 will dramatically undercut current Opus pricing while matching its performance.

The Rumor

Claimed Sonnet 5 Pricing:

• Input: $1.50/million tokens (vs Opus $15)

• Output: $7.50/million tokens (vs Opus $75)

Performance Claims

The Fennec leak suggests Sonnet 5 achieves:

• 80.9% SWE-bench (matching Opus 4.5's launch score)

• Improved reasoning capabilities

• Better speed than current Sonnet

Why This Makes Sense

1. Efficiency Improvements - Better inference optimization

2. Market Pressure - GPT-5.2 at $1.75 input forcing competitive pricing

3. Historical Pattern - Each Sonnet has matched previous Opus

Cost Comparison

10M tokens/month:

Model

Current Cost

Sonnet 5 (est)

Opus 4.5

$900

N/A

Sonnet 4.5

$180

N/A

Sonnet 5

N/A

~$100

Conclusion

While unconfirmed, the Sonnet 5 pricing rumor aligns with market pressures and historical patterns. If true, it would represent significant value for developers.