Head to head · October 2026

Claude Sonnet 5.5 vs Claude Haiku 4.5 API pricing

Claude Haiku 4.5 costs 2.0 times less per token at an 80/20 mix. Input costs 2.0x more on Claude Sonnet 5.5. Output costs 2.0x more on Claude Sonnet 5.5.

Anthropic

Claude Sonnet 5.5

Daily coding in Cursor, Cline and Claude Code.

Vendor: Anthropic
Type: Frontier
SayGM in / out: $1.78 / $8.89
OpenRouter in / out: $2.11 / $10.55
Blended, 80/20: $3.202
Per 100M tokens: $320
Output share of bill: 56%
SayGM vs OpenRouter: 16% lower

Anthropic

Claude Haiku 4.5

Classification, extraction, high-volume pipelines.

Vendor: Anthropic
Type: Frontier
SayGM in / out: $0.89 / $4.45
OpenRouter in / out: $1.06 / $5.28
Blended, 80/20: $1.602
Per 100M tokens: $160
Output share of bill: 56%
SayGM vs OpenRouter: 16% lower

§ 01

Monthly bill at three usage levels

Both models on SayGM. The bars show how the price ratio turns into dollars as volume grows.

Fig. 1Monthly bill at three usage levels

Claude Sonnet 5.5 on SayGM
Claude Haiku 4.5 on SayGM

Side project5M in · 1M out

$18

$8.90

Production app50M in · 15M out

$222

$111

High volume500M in · 100M out

$1,779

$890

Show data as a table

	Claude Sonnet 5.5 on SayGM	Claude Haiku 4.5 on SayGM
Side project (5M in · 1M out)	$18	$8.90
Production app (50M in · 15M out)	$222	$111
High volume (500M in · 100M out)	$1,779	$890

Usage is millions of input and output tokens per month. No caching discount applied. Source: published rate cards, October 2026 snapshot. Current prices on saygm.com.

§ 02

Verdict

A common pattern is to send routine requests to Claude Haiku 4.5 and escalate to Claude Sonnet 5.5 on failure or low confidence. On one key, that is a model name change per request rather than a second provider account.

§ 03

Per-token prices

OpenRouter figures include its 5.5% top-up fee.

USD per million tokens, input and output. OpenRouter includes its 5.5% top-up fee. Snapshot from October 2026.
Model	SayGMin / out	OpenRouterin / out, fee incl.	SayGM vs OpenRouter80/20 blend
Claude Sonnet 5.5Anthropic	$1.78 / $8.89	$2.11 / $10.55	16% lower
Claude Haiku 4.5Anthropic	$0.89 / $4.45	$1.06 / $5.28	16% lower

Current SayGM rates

§ 04

Claude Sonnet 5.5 vs Claude Haiku 4.5 questions

Which is cheaper, Claude Sonnet 5.5 or Claude Haiku 4.5?

Claude Haiku 4.5 is about 2.0 times cheaper than Claude Sonnet 5.5 at an 80/20 input to output mix on SayGM, as of October 2026.

How much do Claude Sonnet 5.5 and Claude Haiku 4.5 cost on OpenRouter?

Including the 5.5 percent top-up fee, Claude Sonnet 5.5 costs $2.11 input and $11 output per million tokens, and Claude Haiku 4.5 costs $1.06 and $5.28.

Can I use Claude Sonnet 5.5 and Claude Haiku 4.5 with one API key?

Yes. SayGM serves both through their native APIs on a single key, so simple tasks can go to Claude Haiku 4.5 and hard ones to Claude Sonnet 5.5, or both can run in a cascade model.

§ 05