---
title: "Compare alternatives to Claude Sonnet 5.5 · Undominated.ai"
canonical: https://undominated.ai/alternatives/anthropic__claude-sonnet-5.5/
description: "12 alternatives score at least as high as Claude Sonnet 5.5 and cost no more under at least one listed workload. 3 preserve recorded capabilities; 9 have named trade-offs."
---

# Compare alternatives to Claude Sonnet 5.5 · Undominated.ai

> 12 alternatives score at least as high as Claude Sonnet 5.5 and cost no more under at least one listed workload. 3 preserve recorded capabilities; 9 have named trade-offs.

# Alternatives to Claude Sonnet 5.5

Anthropic · LMArena 1466.6 · $4.00/M on a balanced workload · prices as of 2026-10-06

 [Compare models](https://undominated.ai/compare/) Comparison context

Choose up to three standard models in Compare.

Requirements and prompt length apply in Compare. This page keeps its stated price basis and workload controls.

## 3 models are higher-scoring or cheaper, with neither dimension worse.

Of the 144 models carrying both an independent score and a published price at the same delivery mode, **12** score at least as high as Claude Sonnet 5.5 and cost no more under at least one listed workload, with at least one of those dimensions improved. **3** match or beat its recorded context, maximum output, input modes, tool use and extended reasoning. **9** have a recorded capability loss, named on every row.

Dominance is not a property of a model. It is a property of a model, a capability lens and a workload, and all three are named on every row. Scores are LMArena Elo, used under CC BY 4.0 from the official dataset; prices are blended per million tokens. A higher score is not a drop-in replacement.

This page is built only while a candidate improves score or price without worsening the other under a listed workload. When that comparison no longer holds, it is not generated.

## Where it holds

| Workload | Claude Sonnet 5.5 $/M | Recorded capabilities preserved | Recorded capability losses |
| --- | --- | --- | --- |
| Balanced | $4.00 | 3 | 9 |
| Summarise | $1.89 | 3 | 9 |
| Chat | $4.66 | 3 | 8 |
| Code gen | $6.66 | 3 | 8 |
| Agentic | $2.13 | 3 | 8 |

Workload mixes are defined on the [methodology page](/methodology/). Cached input is priced at the cached rate, and reasoning tokens at the worse of the reasoning and output rates.

## What you would be replacing

| Intelligence | 1466.6 |
| --- | --- |
| Context window | 1M |
| Max output | 128K |
| Input modes | text, image, file |
| Tool use | yes |
| Extended reasoning | yes |

Preserving recorded capabilities requires matching or beating these fields. [Full record for Claude Sonnet 5.5](/models/anthropic__claude-sonnet-5.5/), or [check Claude Sonnet 5.5 against the whole catalogue](/check/anthropic__claude-sonnet-5.5/).

## Recorded capabilities preserved 3

Each option has a higher score or a lower price, with neither dimension worse under the listed workloads. It matches or beats Claude Sonnet 5.5 on recorded context, maximum output, input modes, tool use and extended reasoning.

| # | Model | Intelligence | $/M | Holds under |
| --- | --- | --- | --- | --- |
| 1 | [Muse Spark 1.3](/models/meta__muse-spark-1.3/) Meta | 1489.9 +23.3 | $2.00 | Balanced −50% Summarise −42% Chat −55% Code gen −55% Agentic −51% |
| 2 | [Muse Spark 1.2](/models/meta__muse-spark-1.2/) Meta | 1483.2 +16.6 | $2.00 | Balanced −50% Summarise −42% Chat −55% Code gen −55% Agentic −51% |
| 3 | [Muse Spark 1.1](/models/meta__muse-spark-1.1/) Meta | 1479.2 +12.6 | $2.00 | Balanced −50% Summarise −42% Chat −55% Code gen −55% Agentic −51% |

## Alternatives with recorded capability losses 9

These improve score or price without worsening the other under the listed workloads, but reduce at least one recorded capability. Read the last column before switching.

| Model | Intelligence | $/M | Holds under | Recorded capability loss |
| --- | --- | --- | --- | --- |
| [MiMo-V2.6-Pro](/models/xiaomi__mimo-v2.6-pro/) Xiaomi | 1491 +24.4 | $0.540 | Balanced −87% Summarise −82% Chat −90% Code gen −90% Agentic −89% | no file input |
| [Gemini 3.8 Flash](/models/google__gemini-3.8-flash/) Google | 1497 +30.4 | $3.00 | Balanced −25% Summarise −25% Chat −25% Code gen −25% Agentic −25% | 128K → 66K max output |
| [Gemini 3.7 Flash](/models/google__gemini-3.7-flash/) Google | 1487 +20.4 | $3.00 | Balanced −25% Summarise −25% Chat −25% Code gen −25% Agentic −25% | 128K → 66K max output |
| [Gemini 3.6 Flash](/models/google__gemini-3.6-flash/) Google | 1479.5 +12.9 | $1.50 | Balanced −63% Summarise −63% Chat −63% Code gen −63% Agentic −63% | 128K → 66K max output |
| [Gemini 3.5 Flash](/models/google__gemini-3.5-flash/) Google | 1477.7 +11.1 | $3.38 | Balanced −16% Summarise −21% Chat −12% Code gen −11% Agentic −14% | 128K → 66K max output |
| [GLM 5.3 Flash](/models/z-ai__glm-5.3-flash/) Z.ai | 1469.6 tie | $0.238 | Balanced −94% Summarise −93% Chat −95% Code gen −95% Agentic −94% | no file input |
| [GLM 5.3](/models/z-ai__glm-5.3/) Z.ai | 1471.4 tie | $1.00 | Balanced −75% Summarise −82% Chat −69% Code gen −68% Agentic −69% | no image, file input |
| [GLM 5.2](/models/z-ai__glm-5.2/) Z.ai | 1470.4 tie | $1.12 | Balanced −72% Summarise −78% Chat −67% Code gen −66% Agentic −67% | no image, file input |
| [Kimi K3](/models/moonshotai__kimi-k3/) Moonshot AI | 1475.9 tie | $3.76 | Balanced −6% Summarise −35% | no file input |

## What this compares, and what it leaves out

 - Quality is LMArena Elo, used under CC BY 4.0 from the official dataset. The 95% confidence interval on a difference between two scores is about ±10.47 points, so a gap smaller than that is marked *tie* rather than an improvement — see [significance bands](/significance/).
 - 204 further models at this delivery mode carry a price but no independent score. They are absent from the comparison in both directions — unrated is not a zero, and an unmeasured model is neither an alternative nor a worse buy.
 - Retired models are never offered as an alternative, and a model only competes against its own delivery mode: batch trades latency for price, so it is not a like-for-like swap.
 - Nothing here measures latency, throughput, rate limits or how a model behaves on your prompts. Two models with the same index score are not interchangeable.
 - Models with no higher-scoring or cheaper alternative that is no worse on the other axis are on the [value frontier](/frontier/). Models with such an alternative are [listed here](/alternatives/).

## Continue your investigation

 - [Check requirements](/check/)
- [Compare exact differences](/compare/)
- [Set a quality floor](/cheapest-at/)
- [Inspect tier boundaries](/cliffs/)