Claude Model Picker

Pick the right Claude model for the task, not out of habit

Most people who overspend on Claude do it in one of two ways: they default to the biggest model 'just in case', or they cling to the smallest one to save money and then fight its limits. Both are the wrong default. The current Claude 4 family is a ladder - Haiku 4.5 for fast, cheap, high-volume work, Sonnet 4.x as the balanced daily driver, and Opus 4.x for the genuinely hard reasoning where a wrong answer is expensive. The picker above turns four honest answers about your task into a deterministic recommendation, with the reasoning shown so you can sanity-check it.

The three models, in plain terms

• Claude Opus 4.x - the heavyweight. Deepest reasoning, best on subtle bugs, complex refactors, and novel architecture. Highest cost per token and slowest, so reach for it when reasoning is the bottleneck, not by default.
• Claude Sonnet 4.x - the default daily driver. The balance of capability, speed, and cost that fits the large majority of coding work. If you are unsure, start here.
• Claude Haiku 4.5 - the fast, cheap workhorse. Best for simple, high-volume, or latency-sensitive tasks: quick edits, formatting, classification, boilerplate, and tight loops.

How the picker decides

The logic is deterministic and transparent. Task difficulty is the strongest signal - hard tasks push toward Opus, moderate toward Sonnet, simple toward Haiku. Budget sensitivity, speed need, and volume then nudge the result: tight budgets, latency pressure, and high volume all pull toward the lighter, cheaper end, while a flexible budget lets capability win. Sonnet carries a small default bias because it is the safest fallback when signals are mixed. The 'why this pick' panel lists every factor that moved the result, so the recommendation is never a black box.

When Opus is worth the premium

Opus costs more per token and runs slower, so the question is not 'is it the best model' - it is 'does this task need it'. It does when the failure mode is expensive: a subtle concurrency bug, a large refactor where a wrong assumption cascades, an unfamiliar domain where reasoning depth prevents a costly wrong turn. In those cases a single avoided rewrite pays for the premium many times over. For routine feature work, Sonnet usually hits the same quality bar for less.

When Haiku is the smart choice

Haiku is not just the budget option - it is the correct option for a large class of work. If you are running many calls, doing simple transformations, building tight interactive loops, or care most about latency, Haiku's speed and cost are exactly what you want, and the heavier models would be waste. High-volume automation in particular multiplies per-token cost, so the model choice there has an outsized effect on the bill.

Match the model to the moment, not the project

The best operators do not pick one model for a whole project - they switch by task. Plan and architect on Opus, build features on Sonnet, run the repetitive edits on Haiku, all within the same day. Claude Code lets you switch models directly, so treat model choice as a per-task knob, not a one-time setting. The picker is for the moments you are unsure; over time the mapping becomes intuition.

A note on pricing and availability

This tool describes relative cost qualitatively - Haiku cheapest, Sonnet mid, Opus most capable and most expensive - because exact per-token prices change and belong on Anthropic's official pricing page. Model versions also advance over time within each tier. Use the recommendation as a strong default, then confirm the current model names and rates against the official source before committing to a workflow or a budget.