How to pick a Claude model and plan: Sonnet 5.5, Opus 5.5, Pro and Max
Choose between Claude Sonnet 5.5 and Opus 5.5, read your usage meter, and understand what independent testing says about how far a Claude plan goes.
8 min · Updated October 20, 2026 · Tools: Claude, Claude Sonnet 5.5, Claude Opus 5.5
- 1Sort your work into routine and hard. Routine work is drafting emails, cleaning up spreadsheets, fixing straightforward bugs and building documents or slides. Hard work needs judgment. Anthropic says Sonnet is for tasks that need execution more than judgment.
- 2Default to Sonnet 5.5 for routine work. Anthropic positions Sonnet 5.5 as the practical everyday model: more than 30% faster than Sonnet 5 and up to 30% cheaper per task.
- 3Switch to Opus 5.5 for harder problems. Save Opus for tasks where you need more intelligence and judgment. On the API it costs about twice as much as Sonnet 5.5.
- 4Start on the $20 plan. Claude Pro costs $20 a month. Use it for a few weeks and note how often you hit the limit before considering a bigger plan.
- 5Read the usage meter. The meter shows percent used over a 5-hour window and a 7-day window. Check it before a big project, not halfway through it.
- 6Upgrade only after you hit limits. Max 20x costs $200 a month. Move up when you regularly run out, not before.
- 7Recheck every month. Providers can change limits quietly. A plan that felt roomy last month may not be the same this month.
Claude has two main tiers for everyday use, and a plan ladder from $20 to $200 a month. The right choice comes down to two questions: how hard is the work, and how often do you hit the limit?
Sonnet or Opus
Anthropic launched Claude Sonnet 5.5 on September 28, 2026. Its pitch is most of Opus's smarts at a lower price.
| Sonnet 5.5 | Opus 5.5 | |
|---|---|---|
| API input price | $2 per million tokens | About twice that |
| API output price | $10 per million tokens | About twice that |
| Best for | Routine tasks that need execution | Hard problems that need judgment |
| Speed | More than 30% faster than Sonnet 5 | Not stated |
Sonnet 5.5 does not push Anthropic's frontier forward. It is the first Sonnet model to ship with cybersecurity safeguards that were previously reserved for Anthropic's most capable models. Full details: Claude Sonnet 5.5 launch.
A simple rule: start every task on Sonnet 5.5. If the result is shallow or keeps missing the point, rerun it on Opus 5.5.
How far does a plan go?
You do not see a token allowance. You see a meter from 0 to 100% over a 5-hour window and a 7-day window. Research firm SemiAnalysis worked backward from that meter and estimated, on a heavy agentic workload, what each plan would cost at pay-per-use prices:
| Plan | Price | Estimated API-equivalent value |
|---|---|---|
| Claude Pro (Opus 5.5) | $20 | $1,178 |
| Claude Max 20x (Opus 5.5) | $200 | $11,726 |
Its headline: Claude plans gave about 5x the value of the matching ChatGPT plans on everyday models. Read the caveats in our story, Claude plans give about 5x more AI per dollar. These are estimates of private meters that can shift at any time.
Habits that stretch your limit
- Pick the model by task. Heavy use of the top model drains the meter faster. SemiAnalysis noted that one top-tier model can only use 50% of a plan's limit.
- Check the meter before a big job.
- Watch for changes. Limits can change quietly in either direction.
For choosing between assistants, see how to choose an AI assistant. For privacy settings, see how to keep your data private in AI chatbots.
Got questions?
Quick answers, plain wordsWhat is Claude Sonnet 5.5 best at?
Anthropic says it is better than its predecessor at coding, completing scoped tasks, and creating polished documents, slides and spreadsheets. It is positioned as the practical option, not the smartest model Anthropic can build.
How much does Sonnet 5.5 cost on the API?
$2 per million input tokens and $10 per million output tokens, half of Opus 5.5's rate, according to CNBC. Chat plans are priced separately.
How much does a Claude plan include?
Anthropic does not publish exact token counts. SemiAnalysis estimated that Claude Pro with Opus 5.5 returned $1,178 of API-equivalent usage a month, and Max 20x returned $11,726. Those are one firm's estimates and limits can change.
Is Claude really five times better value than ChatGPT?
SemiAnalysis found about 5x the API-equivalent value on the everyday models of each company. Other yardsticks differ: Artificial Analysis found GPT-6.1 Sol far cheaper than Opus 5.5 per finished task at API prices. Treat it as a snapshot.
Can my plan's limits change without notice?
Yes. While testing, SemiAnalysis found one of three identical accounts had about 20% lower limits. The provider called it a tiny A/B test.
Sources
Settings and prices change. We check guides against these sources and update the date above when we do.