What is the best alternative to GPT-6.1 Terra?

Claude Opus 5 is the closest model that scores higher on the BenchLeader Index (65.4 against 65.2). For less money, Gemini 3.7 Flash scores 62.2 at $1.50 per 1M tokens.

Is there a cheaper alternative to GPT-6.1 Terra?

Yes: Gemini 3.7 Flash (62.2, $1.50), Gemini 3.8 Flash (61.9, $1.50) and Gemini 3.6 Flash (61.3, $1.50), each within 4 Index points and cheaper than GPT-6.1 Terra's $2.00.

Is there an open-source alternative to GPT-6.1 Terra?

The best open-weights models on the BenchLeader Index are Kimi K3 (62.1), GLM-5 (60.2) and GLM 5.2 (60.1). You can download and run them yourself; check each licence on its model page.

How are these alternatives chosen?

From the models ranked on the BenchLeader Index today: the ones just above GPT-6.1 Terra, cheaper ones within 4 points, ones at least 1.5× as fast within 4 points, and the best open-weights models. Prices are list prices blended three input tokens to one output.

OpenAI

GPT-6.1 Terra alternatives

Data as of 2 Nov 2026 · ranked on the BenchLeader Index

As of 2 Nov 2026, GPT-6.1 Terra by OpenAI scores 65.2 on the BenchLeader Index at $2.00 per 1M tokens blended. Claude Opus 5 scores higher (65.4); Gemini 3.7 Flash is the best cheaper model within 4 points (62.2 at $1.50); Gemini 3.5 Flash is at least 1.5× as fast at a similar score; Kimi K3 is the best open-weights option (62.1).

Scores higher

The closest models above GPT-6.1 Terra on the Index.

Claude Opus 5 Anthropic compare65.4 · $10.00
GPT-5.6 Sol OpenAI compare65.4 · $8.00
Gemini 4 Argon Google compare65.9 · $4.00

Cheaper, nearly as good

Within 4 Index points, for less per token.

Gemini 3.7 Flash Google compare62.2 · $1.50
Gemini 3.8 Flash Google compare61.9 · $1.50
Gemini 3.6 Flash Google compare61.3 · $1.50

Faster

At least 1.5× the output speed, within 4 points.

Gemini 3.5 Flash Google compare62.5 · $3.38
Muse Spark 1.1 Meta compare62.2 · $2.00
Muse Spark 1.3 Meta compare61.9 · $2.00

Open weights

The best models whose weights you can run yourself.

Kimi K3 Moonshot AI compare62.1 · $6.00
GLM-5 Zhipu AI60.2 · $1.55
GLM 5.2 Zhipu AI compare60.1 · $2.15

Every alternative side by side

Model	Index	$ / 1M blended	Tokens / s	Why
GPT-6.1 Terra (this model)	65.2	$2.00	107	–
Gemini 4 Argon	65.9	$4.00	83	scores higher
Claude Opus 5	65.4	$10.00	53	scores higher
GPT-5.6 Sol	65.4	$8.00	127	scores higher
Gemini 3.5 Flash	62.5	$3.38	190	faster
Gemini 3.7 Flash	62.2	$1.50	91	cheaper
Muse Spark 1.1	62.2	$2.00	206	faster
Kimi K3	62.1	$6.00	66	open weights
Gemini 3.8 Flash	61.9	$1.50	131	cheaper
Muse Spark 1.3	61.9	$2.00	194	faster
Gemini 3.6 Flash	61.3	$1.50	197	cheaper
GLM-5	60.2	$1.55	62	open weights
GLM 5.2	60.1	$2.15	89	open weights

Prices are list prices blended three input tokens to one output; speeds are measured medians, credited on each model page. The Index is BenchLeader's own, from independent benchmarks.

Questions people ask

What is the best alternative to GPT-6.1 Terra?: Claude Opus 5 is the closest model that scores higher on the BenchLeader Index (65.4 against 65.2). For less money, Gemini 3.7 Flash scores 62.2 at $1.50 per 1M tokens.
Is there a cheaper alternative to GPT-6.1 Terra?: Yes: Gemini 3.7 Flash (62.2, $1.50), Gemini 3.8 Flash (61.9, $1.50) and Gemini 3.6 Flash (61.3, $1.50), each within 4 Index points and cheaper than GPT-6.1 Terra's $2.00.
Is there an open-source alternative to GPT-6.1 Terra?: The best open-weights models on the BenchLeader Index are Kimi K3 (62.1), GLM-5 (60.2) and GLM 5.2 (60.1). You can download and run them yourself; check each licence on its model page.
How are these alternatives chosen?: From the models ranked on the BenchLeader Index today: the ones just above GPT-6.1 Terra, cheaper ones within 4 points, ones at least 1.5× as fast within 4 points, and the best open-weights models. Prices are list prices blended three input tokens to one output.