HEAD-TO-HEAD · FLAGSHIP-TIER · VERIFIED OCTOBER 5, 2026

Claude Opus 5.5 vs Claude Opus 4.8: which is actually cheaper?

Claude Opus 5.5 and Claude Opus 4.8 are both current Anthropic flagship-tier models, but Opus 5.5 is the newer, cheaper release. At $4/M input and $20/M output versus $5/M input and $25/M output for Opus 4.8, Opus 5.5 undercuts its predecessor by a flat 20% on every token in both directions.

Spec	Claude Opus 5.5	Claude Opus 4.8
Input / 1M tokens	$4.00	$5.00
Output / 1M tokens	$20.00	$25.00
Context window	1M	1M

The output price gap

Output tokens are where the real money goes on both models, priced at 5x their respective input rates. Opus 5.5 charges $20/M for output against Opus 4.8's $25/M — a $5/M gap that compounds quickly on reasoning-heavy or long-generation workloads like agentic coding, where output volume typically dwarfs input.

Context window

Both models ship with a 1M token context window, so there's no capacity trade-off between them — the pricing gap is the only meaningful variable for workloads that fit comfortably within that window.

Worked example

At 100M input and 30M output tokens in a month: Opus 5.5 costs (100 x $4) + (30 x $20) = $400 + $600 = $1,000. Opus 4.8 costs (100 x $5) + (30 x $25) = $500 + $750 = $1,250. That's a $250/month savings with Opus 5.5 on this workload, a 20% reduction in total spend.

Prices from the LLM Price Watch daily tracker, 2026-10-05. Prices change; use the calculator with your own usage for an exact comparison, or see the full price table for every tracked model.

Frequently asked questions

Is Claude Opus 5.5 cheaper than Claude Opus 4.8?

Yes. Opus 5.5 costs $4 per million input tokens and $20 per million output tokens, a flat 20% discount versus Opus 4.8's $5/$25 per million. The savings apply uniformly to both input and output, so the percentage discount holds regardless of your input-to-output ratio.

Do Opus 5.5 and Opus 4.8 have the same context window?

Both models offer a 1M token context window, based on current documentation. This means switching from Opus 4.8 to Opus 5.5 for cost savings doesn't require sacrificing any context capacity — it's a straightforward price-for-price downgrade in cost, not capability.

Which model is better for output-heavy workloads like coding agents?

Opus 5.5 has the clear edge for output-heavy workloads since output tokens cost $20/M versus $25/M on Opus 4.8. Agentic coding and long-form reasoning tasks generate disproportionate output volume, so the $5/M gap compounds faster than on input-heavy use cases.

Is Claude Opus 4.8 still worth using instead of Opus 5.5?

Opus 4.8 remains active but costs more per token with no documented context window advantage over Opus 5.5. Unless you have a specific compatibility, benchmark, or regression reason tied to Opus 4.8 specifically, Opus 5.5 is the more cost-effective choice for equivalent flagship-tier work.