THE VERDICT
● Sonnet 5 at $3/$15 — permanent, and still cheaper than Sol at either rate. Add 10 to 35 percent on code for the tokenizer change.
● Sol at $4/$20 — promotional until about 21 November, then $5/$30.
● The rule: price any migration at $5/$30. Three months of savings rarely covers the engineering time.
What each costs now
| Model | Input / 1M | Output / 1M | Permanent? |
|---|
| Claude Sonnet 5 | $3 (was $2) | $15 (was $10) | Yes |
| GPT-5.6 Sol | $4 | $20 | No — until ~21 Nov |
| Sol after November | $5 | $30 | Yes |
| GPT-5.6 Terra | $2 | $12 | Yes |
| GPT-5.6 Luna | $0.20 | $1.20 | Yes |
THE TOKENIZER CHANGE IS NOT IN THE HEADLINE
Sonnet 5 rose 50 percent on the rate card. A tokenizer change landed the same day adding 10 to 35 percent more tokens on code.
Compound them and a coding workload sits 65 to 100 percent above where it did last week. Text-heavy work stays closer to the 50 percent figure.
Which one
| If you are... | Do this |
|---|
| Already on Sonnet 5 | Stay. It is still cheaper than Sol at either rate |
| Tempted by Sol at $4/$20 | Model it at $5/$30. If it still wins, migrate |
| Running high-volume simple tasks | Neither. Luna at $0.20/$1.20 is an order of magnitude below both |
| Feeling the tokenizer increase | Trim context between turns before switching provider |
FAQ
Which is cheaper now?
Sonnet 5 at $3 and $15, against Sol at $4 and $20 promotionally or $5 and $30 standard. Factor the tokenizer change if your input is mostly code.
When does Sol pricing revert?
Around 21 November 2026, three months from the 21 August cut.
Does the Sonnet 5 rise affect Claude Pro?
No. Consumer subscriptions are unaffected. This is API pricing only.