---
title: "Claude Opus 5 vs Gemini 3.8 Flash — which is worth buying · Undominated.ai"
canonical: https://undominated.ai/compare/anthropic__claude-opus-5--vs--google__gemini-3.8-flash/
description: "Claude Opus 5 versus Gemini 3.8 Flash: capability, price, and whether either strictly dominates the other. Unrated stays unrated."
---

# Claude Opus 5 vs Gemini 3.8 Flash — which is worth buying · Undominated.ai

> Claude Opus 5 versus Gemini 3.8 Flash: capability, price, and whether either strictly dominates the other. Unrated stays unrated.

# Claude Opus 5 versus Gemini 3.8 Flash

Neither strictly dominates the other on this workload.

 [Claude Opus 5](/models/anthropic__claude-opus-5/)

General

 **

1504.9

Effective $/M

 **

$10.00/M

 [Gemini 3.8 Flash](/models/google__gemini-3.8-flash/)

General

 **

1494.7

Effective $/M

 **

$1.50/M

| | Claude Opus 5 | Gemini 3.8 Flash |
| --- | --- | --- |
| LMArena | 1504.9 | 1494.7 |
| Document | 1516.3 | — |
| Arena | 1504.9 | 1494.7 |
| Effective $/M | $10.00 | $1.50 |
| Context | 1M | 1.0M |

## Questions this page answers

### Is Claude Opus 5 both better and cheaper than Gemini 3.8 Flash?

Neither strictly dominates the other on this workload.

### Does a missing score count as zero?

No. Unrated is not a score of zero. No quality bar is drawn for a missing score.