GPT-6.1 Terra vs Qwen3.8 Flash

vs

Which one, when

For prompts up to 272000 input tokens, qwen3.8-flash has lower input and output rates and accepts video. Choose gpt-6.1-terra for the OpenAI model positioned for visual reasoning and computer use, after checking that its higher cost pays off on your tasks.

Benchmarks

GPT-6.1 Terra: the vendor has not published benchmark scores.

Above averageNo peer higherQwen3.8 Flash12 / 163 / 16
GPT-6.1 Terra Qwen3.8 Flash other models measured peer average ★ no peer scored higher
SWE-Bench Pro
N/A
62.5%
OSWorld 2.0 partial
N/A
52.3%
JobBench
N/A
55.7%
GPQA Diamond
N/A
91.7%
ERQA
N/A
no peer scored higher 72.3%
Agents' Last Exam Pass
N/A
24.3%
LVBench
N/A
76.6%

Vendor-published: Alibaba (Qwen) Anthropic ByteDance DeepSeek Google MiniMax Moonshot OpenAI Tencent Z.ai

Pricing

GPT-6.1 Terra Qwen3.8 Flash Δ
Input / 1M tokens $1 $0.15 6.7×
Output / 1M tokens $5 $0.47 11×
Cache read / 1M tokens $0.05 $0.016 3.1×
Cache write 1.25x (30m) / 2.5x (12h) 1.25x -

Rates from the live catalogue at build time; each model page carries the current rate card.

Where they sit · input price per 1M tokens across all 80 chat models on this billing unit (log scale)

GPT-6.1 Terra · $1 Qwen3.8 Flash · $0.15
$0.05 · Qwen3 VL Flash $30 · GPT-5.4 Pro

Capabilities

GPT-6.1 Terra Qwen3.8 Flash
Tool calling yes yes
Thinking control configurable configurable
Structured output yes yes
Prompt caching implicit + explicit implicit + explicit
Cache lifetime at least 30m by default, 12h option on the Responses API explicit: 5m, reset on hit
Minimum cached prefix 1,024 tokens 1,024 tokens

Specs

GPT-6.1 Terra Qwen3.8 Flash
Input modalities text image text image video
Output modalities text text
Released 2026-10-26 2026-08-27
Knowledge cutoff 2026-06 -
Context window 1.1M 1M
Max output 128K 131K
Thinking parameter reasoning.effort
  • enable_thinking
  • thinking_budget
  • preserve_thinking
Accepted values
reasoning.effort
  • none
  • low
  • medium
  • high
  • xhigh
  • max
enable_thinking
  • true
  • false
thinking_budget
  • in tokens
preserve_thinking
  • true
  • false
Default medium

on

qwen3.8-flash is hybrid thinking with thinking enabled by default, thinking_budget defaults to the 262,144-token chain maximum, and preserve_thinking is off

Specs are transcribed from each vendor’s documentation; a row a vendor does not publish is left out rather than inferred. Full sources: GPT-6.1 Terra · Qwen3.8 Flash

One prompt, both models, measured through the gateway

PROMPT Explain to a CFO, in exactly three sentences, why our LLM bill doubled after we enabled reasoning. CHECK exactly 3 sentences

GPT-6.1 Terra passed · 3 sentences

Enabling reasoning caused the model to process additional internal tokens before producing each answer, even though those tokens are not visible to users. Those tokens are generally billable, increasing the cost per request and potentially doubling the bill even if usage stayed the same. To confirm the cause, compare request counts, model pricing, and token usage—including reasoning tokens—before and after the change.

out 196 tok (+115 thinking) latency 4.6 s

Qwen3.8 Flash passed · 3 sentences

Enabling reasoning makes the model spend additional output tokens to plan and validate answers before responding, and those tokens are billed. It also increases compute and latency per request, so each task consumes more capacity than a non-reasoning call. As a result, billable tokens and compute roughly doubled, directly driving the higher invoice.

out 330 tok (+262 thinking) latency 8.9 s

Instruction following (exactly three sentences, so countable), audience shaping (CFO register), and the hidden-thinking billing gap the token meters below expose.

PROMPT This function is supposed to return the longest run of consecutive equal items, but callers report it is off by one on single-element inputs and misses runs that end at the last index. Fix it and explain the bug in one paragraph. CHECK fix passes tests

GPT-6.1 Terra passed · 8/8 cases

```python def longest_run(xs): if len(xs) == 0: return 0 best = cur = 1 for i in range(1, len(xs)): if xs[i] == xs[i - 1]: cur += 1 else: cur = 1 best = max(best, cur) return best ``` The original code counted matching *adjacent pairs* rather than items, so every nonempty run was undercounted by one, including a single-element input. It did update `best` for matches at the last index, but still undercounted those runs. The fix starts each run at length one and updates `best` as the run grows.

out 331 tok (+172 thinking) latency 6.3 s

Qwen3.8 Flash passed · 8/8 cases

```python def longest_run(xs): if not xs: return 0 best = 1 cur = 1 for i in range(1, len(xs)): if xs[i] == xs[i - 1]: cur += 1 else: cur = 1 best = max(best, cur) return best ``` The bug is that the original version counts adjacent equal pairs rather than items in a run, starting both `cur` and `best` at `0`, and it resets `cur` to `0` after a mismatch, thereby discarding the first element of the new run. That makes single-element inputs return `0`, and because every run is effectively measured in “steps” between equal elements, the last element is not counted—particularly noticeable when the longest run ends at the final index.

out 2123 tok (+1933 thinking) latency 43.8 s

Whether the fix is actually correct (runnable), explanation density, and token efficiency on a bounded task.

PROMPT Extract a JSON object with fields {company, quarter, revenue_usd_m, growth_pct, guidance} from this text. Use null for anything not stated; add no other fields. CHECK valid JSON, schema exact

GPT-6.1 Terra passed · 5/5 fields, guidance "Withheld pending the Q4 close"

{ "company": "Meridian Robotics", "quarter": "September quarter", "revenue_usd_m": null, "growth_pct": null, "guidance": "Withheld pending the Q4 close" }

out 317 tok (+261 thinking) latency 6.9 s

Qwen3.8 Flash passed · 5/5 fields, guidance null

{ "company": "Meridian Robotics", "quarter": "September quarter", "revenue_usd_m": 412, "growth_pct": 11, "guidance": null }

out 519 tok (+463 thinking) latency 10.5 s

Schema obedience (no invented fields), hallucination pressure (guidance is explicitly withheld), and structured-output path differences.

PROMPT Write a 120-word product announcement for an API gateway feature that caches prompts across providers. Forbidden words: "seamless", "unlock", "game-changer", "revolutionize", "empower". Exactly one sentence must be a question. CHECK 120 words, 0 banned words

GPT-6.1 Terra passed · 120 words, 0 banned, 1 question

Meet Prompt Cache, a new API gateway feature that stores reusable prompts across providers, helping teams reduce latency and control costs without changing how they build. When a request matches a cached prompt, the gateway retrieves the stored result instead of sending the same work again. Need to route traffic between models or vendors? Prompt Cache works across supported providers, giving your applications a consistent caching layer as your stack evolves. Set expiration policies, monitor cache performance, and choose which requests qualify through familiar gateway controls. Your team can spend less time repeating requests and more time improving the experiences customers rely on. Start using Prompt Cache today and make every request work harder for your application and your budget.

out 579 tok (+440 thinking) latency 9.1 s

Qwen3.8 Flash passed · 120 words, 0 banned, 1 question

We are announcing prompt caching across providers in our API gateway. Store approved prompt outputs once and reuse them across supported model providers, cutting latency, cost, and duplicate token spend. The feature matches identical requests, checks validity, and returns cached results while preserving routing controls. Developers keep existing endpoints; the gateway manages storage, invalidation, and provider differences. This reduces noisy repeat calls, improves steady responses, and frees teams to focus on better agent workflows. OpenAI, Anthropic, Google, Mistral, and custom routes are supported. Cache hits appear in analytics with latency, token, and cost reductions visible. Check retention and privacy rules before enabling it. Ready to add cache controls to your gateway? Enable it in settings and watch spend drop now.

out 5958 tok (+5805 thinking) latency 88.8 s

Constraint obedience (word budget, banned-word list, the single question), style fingerprint, and length control.

Switch between them with one line

Both ids are in every tab below; the highlighted pair of lines is the only edit. Same endpoint, same key, same request shape.

from openai import OpenAI

client = OpenAI(
    base_url="https://synthorai.io/v1",
    api_key="sk-syn-...",
)

resp = client.chat.completions.create(
    model="gpt-6.1-terra",
    # model="qwen3.8-flash",  # uncomment this line, comment the one above
    messages=[{"role": "user", "content": "Summarize this diff"}],
    reasoning_effort="medium",
)
print(resp.choices[0].message.content)

Get your API key →

FAQ

Which is cheaper, GPT-6.1 Terra or Qwen3.8 Flash?

Qwen3.8 Flash is cheaper on the "Input / 1M tokens" row ($0.15 vs $1, 6.7× apart). Other rows may point the other way; the table above carries the full rate card, and real cost depends on your mix.

Can I A/B test GPT-6.1 Terra against Qwen3.8 Flash without two integrations?

Yes. Both are served through the same OpenAI-compatible endpoint with one API key. Switching is a one-line change to the model id, so you can route a fraction of traffic to each and compare bills directly.

Do GPT-6.1 Terra and Qwen3.8 Flash support prompt caching?

Yes. Both bill cache reads below their input rate, so warm-prefix workloads cost less than the list rates suggest. The exact cache-read rows are in the pricing table above.

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