← comparisons · head to head
Gemini 3.8 Flash vs Claude Opus 5
Of the 3 public leaderboards that rate both, Gemini 3.8 Flash scores higher on 1 and Claude Opus 5 on 2. On the ArtificialWatch Index, which takes the median of each model's percentile across the boards that score it, Gemini 3.8 Flash is at 43.7 and Claude Opus 5 at 77.5 (out of 100). On each maker's API, Gemini 3.8 Flash costs $0.75 / $3.75 per 1M tokens (input / output) and Claude Opus 5 $5 / $25.
Scores as published by each board; table composed November 10, 2026.
Get the next launch alert, free →
Leaderboard by leaderboard
| Board | Gemini 3.8 Flash | Claude Opus 5 | Higher |
|---|---|---|---|
| LMArena Elo (community votes) | 1,583.8 | 1,690.8 | Claude Opus 5 |
| SimpleBench AVG@5 % (private set) | 82.4 | 80.6 | Gemini 3.8 Flash |
| Epoch AI Epoch Capabilities Index (ECI) · many benchmarks on one scale | 158.7 | 164.5 | Claude Opus 5 |
Raw scores are each board's own scale, so compare within a row, not across rows. Full table: the bench index.
For coding
On the ArtificialWatch coding index, Gemini 3.8 Flash is at 40.8 (#26 of 47) and Claude Opus 5 at 85 (#7). Claude Opus 5 scores higher on both coding boards that rate them.
| Coding board | Gemini 3.8 Flash | Claude Opus 5 |
|---|---|---|
| LMArena · Coding | 1,510.6 | 1,531.9 |
| Vals Vibe Code Bench | 78.7 | 88.4 |
Gemini 3.8 Flash at a glance
- Developer
- Status
- Live since September 2, 2026
- API price
- $0.75 input / $3.75 output per 1M tokens · Google, gemini-3.8-flash
- Context window
- 1.05M tokens
Live — GA Sep 2 · $0.75/$3.75 per 1M introductory through Dec 31, identical to 3.7 · 1M in / 64K out · 'our most intelligent Flash model' · 20 days after 3.7.
Gemini 3.8 Flash is GA — same price as 3.7, twenty days later
2026-09-02 · Google released Gemini 3.8 Flash today. The Gemini API changelog for September 2 reads: "Gemini 3.8 Flash generally available (GA): Released gemini-3.8-flash, our most intelligent Flash model, engineered for long-horizon software engineering, autonomous agents, and complex enterprise workflows."
Claude Opus 5 at a glance
- Developer
- Anthropic
- Status
- Live since July 24, 2026
- API price
- $5 input / $25 output per 1M tokens · Anthropic, claude-opus-5
- Context window
- 1M tokens
Live — detected 16:51 UTC Jul 24, alert fired 61s later · superseded by Opus 5.5 on Sep 22 and moved to Anthropic's legacy list; still served at $5/$25, which is now MORE than its successor.
Claude Opus 5 is live — we detected it at 16:51 UTC and had alerts out 61 seconds later
2026-07-24 · Anthropic's Claude Opus 5 went live on the public API today. Our checkers saw the id appear at 16:51:33 UTC, confirmed it on the next 60-second sweep, and the alert blast went out at 16:52:34 — sixty-one seconds from first sighting to inbox.
Gemini 3.8 Flash vs Claude Opus 5: quick answers
Which is better, Gemini 3.8 Flash or Claude Opus 5?
It depends on what you measure. Of the 3 public leaderboards that rate both, Gemini 3.8 Flash scores higher on 1 and Claude Opus 5 on 2. Gemini 3.8 Flash's widest lead is on SimpleBench; Claude Opus 5's widest lead is on LMArena. On the ArtificialWatch Index, which takes the median of each model's percentile across the boards that score it, Gemini 3.8 Flash is at 43.7 and Claude Opus 5 at 77.5 (out of 100).
Which is newer, Gemini 3.8 Flash or Claude Opus 5?
Gemini 3.8 Flash. It went live on September 2, 2026, 40 days after Claude Opus 5 (July 24, 2026).
Which is cheaper, Gemini 3.8 Flash or Claude Opus 5?
Gemini 3.8 Flash is cheaper on both input and output. On each vendor's own API, Gemini 3.8 Flash is $0.75 input / $3.75 output per million tokens and Claude Opus 5 is $5 input / $25 output per million tokens. Prices as published in the models.dev catalog, as of 2026-11-10.
Which has the bigger context window, Gemini 3.8 Flash or Claude Opus 5?
Gemini 3.8 Flash, at 1.05M tokens against Claude Opus 5's 1M, as each vendor lists it.
How do Gemini 3.8 Flash and Claude Opus 5 compare for coding?
On the ArtificialWatch coding index, Gemini 3.8 Flash is at 40.8 (#26 of 47) and Claude Opus 5 at 85 (#7). Claude Opus 5 scores higher on both coding boards that rate them.
Who makes Gemini 3.8 Flash and Claude Opus 5?
Gemini 3.8 Flash is from Google; Claude Opus 5 is from Anthropic.
Where do these numbers come from?
Each score is the leaderboard's own published figure, read by ArtificialWatch (table composed November 10, 2026). Boards measure different things, so raw scores are only comparable within a row.
More comparisons
Hear when the next one drops. Free.
Free: a Chrome push and an email about 15 minutes after a new model answers on a public API. Members get a text or a phone call the moment a launch is confirmed.
- Free forever
- No card
- Unsubscribe in one click
Also: the bench index · API pricing · what a workload costs on each · the wire