Compare / Claude Sonnet 5.5 vs GPT-6.1 Terra
Claude Sonnet 5.5 vs GPT-6.1 Terra
Which is cheaper, which is more capable, and which does better at each kind of work, from 67 results on 4 sources that measured both models.
AnthropicClaude Sonnet 5.5
OpenAIGPT-6.1 Terra
Claude Sonnet 5.5 wins 1119 too close to callGPT-6.1 Terra wins 37
Of the 67 results both models have, the better value on each. Results whose reported ranges overlap are too close to call.
Results as of 5 November 2026 (catalogue release 2026-11-05-44c5fb63d296). See also Anthropic vs OpenAI, every model from both labs.
Claude Sonnet 5.5 or GPT-6.1 Terra? The short answer
Pick GPT-6.1 Terra: it scores higher (Spring Prompt overall 83 against 63) and costs less.
- Spring Prompt overall: Claude Sonnet 5.5 63, GPT-6.1 Terra 83 (out of 100; how the score works).
- GPT-6.1 Terra is cheaper to run: $0.004 against $0.017 per product listing on CatalogBench (4.8 times less).
- GPT-6.1 Terra is newer: released 26 Oct 2026, against 28 Sep 2026 for Claude Sonnet 5.5.
- On our own benchmarks, on the results both models have: GPT-6.1 Terra does better for product listings and marketing planning.
Head to head
63
Spring Prompt overall
83
$4.00
Price per million tokens, blendedlower is better
$2.00
1,000,000
Context window, tokens
1,050,000
Every fact side by side
| Claude Sonnet 5.5 | GPT-6.1 Terra | |
|---|---|---|
| Price per million tokens | $2.00 in · $10.00 out | $1.00 in · $5.00 out |
| Blended (3 in : 1 out) | $4.00 | $2.00 |
| Cheapest host, blended | $4.00 (Amazon Bedrock) | $2.00 (Azure) |
| Cost per product listing (CatalogBench) | $0.017 | $0.004 |
| Cached input, per million | $0.20 cached input | $0.050 cached input |
| Intelligence Index | 56.0 | – |
| Spring Prompt overall | 63 | 83 |
| Output speed, tokens a second | 137 | – |
| Context window | 1,000,000 tokens | 1,050,000 tokens |
| Released | 28 Sep 2026 | 26 Oct 2026 (newer) |
| Weights | Closed | Closed |
| Developer based in | the US | the US |
Prices are the developer's list price where we have read it, otherwise the typical host on OpenRouter; see every model's price. Intelligence and speed from Artificial Analysis.
Which is better for what
Each model's rank among the models on sale today, for each kind of work, from our own benchmarks and licensed sources. Further right is better; the better rank is in green.
Product listingsTurning a sparse product feed and photos into listings that can go live
14 of 27
4 of 27
Decks from an analysisTurning a finished analysis into a deck you could present as it is
5 of 28
6 of 28
User surveysPlanning a user survey and reading its results without being misled
not measured
5 of 17
Marketing planningPlanning a year of ad spend without overspending
6 of 28
1 of 28
Agents and tool useMulti-step tasks with tools: support desks, coding agents, function calls
1 of 160
not measured
Professional workReal tasks from banking, consulting and law, business documents and freelance projects
1 of 51
not measured
Reasoning and knowledgeHard questions across science, maths and general knowledge
2 of 188
not measured
WritingWhat people prefer in blind comparisons, and judged writing quality
33 of 173
not measured
Sticking to the factsSummarising without inventing things, and factual answers
43 of 143
not measured
Speed under pressureGood decisions against a real clock (fast chess)
28 of 31
16 of 31
Their slides, side by side
The same brief for both: Manchester store investment review for Hearthside Coffee, an invented company. First slide of each deck from DeckBench.
From our research
- GPT-6.1 Terra review: close to the top of our business tests at half the price of Sol 5 Nov 2026
- Claude Haiku 5.5 Is Far Better Than Haiku 4.5 at a Tenth of the Price. GPT-6 Luna Still Beats It at Business Work. 8 Oct 2026
- Kimi K3.1 Pro first look: the best open-weight model on our board, and very slow 5 Nov 2026
Every shared result
Each model's best result on every measure both have, grouped by benchmark, with the setting that produced it. Under each measure, every model that benchmark has measured is a grey tick, best to the right, so you can see where the two sit in the field. The headline measures of each benchmark come first; the rest are under "Show all". Green marks the better value; where a source reports ranges that overlap, neither is marked.
| Measure | Claude Sonnet 5.5 | GPT-6.1 Terra |
|---|---|---|
| BulletBench measured by Spring Prompt · 3 results | ||
| Cost per game · Blitz 3+2US dollars, lower is better 10 · 7 of 16 measured | $0.12 | $0.0706 |
| Ladder Elo · Lightning 10+1ladder Elo, higher is better 23 · 17 of 26 measured | 33low reasoning | 491low reasoning |
| Cost per game · Lightning 10+1US dollars, lower is better 20 · 16 of 26 measured | $0.0080low reasoning | $0.0064low reasoning |
| CatalogBench measured by Spring Prompt · 3 results | ||
| Cost per productUS dollars, lower is better 19 · 8 of 28 measured | $0.0172 | $0.0036 |
| Reliably publish-ready% of products, higher is better 16 · 5 of 27 measured | 32.1% | 64.3% |
| Reliably publish-ready · sales brief% of products, higher is better 13 · 2 of 27 measured | 10.7% | 67.9% |
| DeckBench measured by Spring Prompt · 3 results | ||
| Cost per deckUS dollars, lower is better 19 · 15 of 28 measured | $0.15 | $0.0672 |
| Deck ratingrating, higher is betterThe rating weighs each win by how strong the other deck was; the win rate counts wins against whichever decks a model happened to meet, so the two can disagree. 5 · 6 of 28 measured | 1,366 | 1,344 |
| Accurate decks% of tasks, higher is better 8 · 1 of 28 measured | 66.7% | 100.0% |
| ROASBench measured by Spring Prompt · 3 results | ||
| Overall scorescore out of 100, higher is better 6 · 1 of 28 measured | 52.0 | 58.4 |
| Audience scorescore out of 100, higher is better 15 · 1 of 28 measured | 61.8 | 69.4 |
| Business scorescore out of 100, higher is better 4 · 1 of 28 measured | 57.2 | 59.1 |
Show all 67 results (55 more)
| Measure | Claude Sonnet 5.5 | GPT-6.1 Terra |
|---|---|---|
| BulletBench measured by Spring Prompt · 7 results | ||
| Games lost on time · Blitz 3+2% of games, lower is better 9 · 8 of 16 measured | 37.5% | 25.0% |
| Games lost on time · Lightning 10+1% of games, lower is better 25 · 19 of 26 measured | 91.7%low reasoning | 62.5%low reasoning |
| Invalid moves · Blitz 3+2% of moves, lower is better 1 · 1 of 16 measured | 0.0% | 0.0% |
| Invalid moves · Lightning 10+1% of moves, lower is better 1 · 1 of 26 measured | 0.0%low reasoning | 0.0%low reasoning |
| Ladder Elo · Blitz 3+2ladder Elo, higher is better 8 · 6 of 16 measured | 557 | 683 |
| Median move time · Blitz 3+2milliseconds, lower is better 16 · 7 of 16 measured | 8.1 s | 3.7 s |
| Median move time · Lightning 10+1milliseconds, lower is better 26 · 22 of 26 measured | 2.1 slow reasoning | 1.3 slow reasoning |
| CatalogBench measured by Spring Prompt · 28 results | ||
| Channel compliance% of products, higher is better 20 · 27 of 28 measured | 99.4% | 98.2% |
| Channel rules broken% of products, lower is better 22 · 25 of 28 measured | 1.2% | 1.8% |
| Channel rules broken · sales brief% of products, lower is better 14 · 1 of 28 measured | 0.6% | 0.0% |
| Claims to check% of products, lower is better 1 · 1 of 26 measured | 0.0% | 0.0% |
| Claims to check · sales brief% of products, lower is better 16 · 1 of 26 measured | 0.6% | 0.0% |
| Conflicts caught% of conflicts, higher is better 1 · 1 of 28 measured | 100.0% | 100.0% |
| Content quality% of checks, higher is better 18 · 9 of 28 measured | 96.5% | 97.7% |
| Content quality · sales brief% of checks, higher is better 12 · 5 of 28 measured | 97.3% | 98.3% |
| Decision accuracy% of decisions, higher is better 19 · 5 of 28 measured | 95.7% | 98.1% |
| Failed outputs% of products, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Failed outputs · sales brief% of products, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Field accuracy% of missing fields, higher is better 25 · 6 of 28 measured | 91.5% | 94.4% |
| Invented values% of filled values, lower is better 7 · 12 of 28 measured | 0.8% | 1.5% |
| Missing UK information% of products, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Missing UK information · sales brief% of products, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Not findable% of products, lower is better 4 · 25 of 28 measured | 1.2% | 10.7% |
| Not findable · sales brief% of products, lower is better 4 · 27 of 28 measured | 0.6% | 13.7% |
| Publish-ready listings% of products, higher is better 19 · 6 of 28 measured | 46.4% | 74.4% |
| Publish-ready listings · sales brief% of products, higher is better 15 · 3 of 28 measured | 27.4% | 74.4% |
| Time per productseconds, lower is better 8 · 9 of 28 measured | 9.90 | 10.1 |
| Unsupported claims% of products, lower is better 23 · 3 of 28 measured | 39.3% | 0.6% |
| Unsupported claimsclaims per product, lower is better 20 · 4 of 28 measured | 1.08 | 0.03 |
| Unsupported claims · sales briefclaims per product, lower is better 14 · 3 of 28 measured | 1.71 | 0.09 |
| Unsupported claims · sales brief% of products, lower is better 14 · 1 of 28 measured | 59.5% | 1.8% |
| Wrong attributes% of products, lower is better 18 · 5 of 28 measured | 19.1% | 14.9% |
| Wrong attributes · sales brief% of products, lower is better 21 · 7 of 28 measured | 20.8% | 14.9% |
| Wrong category or variant% of products, lower is better 19 · 5 of 28 measured | 3.0% | 1.8% |
| Wrong category or variant · sales brief% of products, lower is better 18 · 5 of 28 measured | 3.0% | 1.8% |
| DeckBench measured by Spring Prompt · 14 results | ||
| Caveat dropped% of tasks, lower is better 14 · 1 of 28 measured | 16.7% | 0.0% |
| Clean layout% of tasks, higher is better 1 · 3 of 28 measured | 100.0% | 83.3% |
| Design quality% of the maximum, higher is better 6 · 5 of 28 measured | 78.5% | 80.8% |
| Draft figure quoted% of tasks, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Findings missing% of tasks, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Head-to-head win rate% of comparisons, higher is betterThe rating weighs each win by how strong the other deck was; the win rate counts wins against whichever decks a model happened to meet, so the two can disagree. 4 · 17 of 28 measured | 84.4% | 48.3% |
| Layout defects% of tasks, lower is better 1 · 3 of 28 measured | 0.0% | 16.7% |
| Misleading metric used% of tasks, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Presentable decks% of tasks, higher is better 2 · 2 of 28 measured | 50.0% | 50.0% |
| Recommendation late or wrong% of tasks, lower is better 12 · 1 of 28 measured | 16.7% | 0.0% |
| Slides needing work% of tasks, lower is better 8 · 8 of 28 measured | 33.3% | 33.3% |
| Time per deckseconds, lower is better 10 · 16 of 28 measured | 83.4 | 135 |
| Unsupported claims% of tasks, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| Unsupported numbers% of tasks, lower is better 1 · 1 of 28 measured | 0.0% | 0.0% |
| ROASBench measured by Spring Prompt · 6 results | ||
| Consistency scorescore out of 100, higher is better 13 · 1 of 28 measured | 28.5 | 48.8 |
| Contribution profitsimulated US dollars, higher is better 15 · 6 of 28 measured | $571,203 | $701,059 |
| Cost of a runUS dollars, lower is better 19 · 10 of 28 measured | $0.42 | $0.11 |
| Months over budgetmonths of 12, lower is better 1 · 1 of 28 measured | 0 | 0 |
| Planning scorescore out of 100, higher is better 3 · 7 of 28 measured | 55.1 | 55.0 |
| Return on ad spendprofit per $1 spent, higher is better 3 · 2 of 28 measured | $0.70 | $0.71 |
Compare them with other models
- Anthropic vs OpenAIEvery model from both labs, best against best
- Claude Sonnet 5.5 vs Claude Opus 5.5Most intelligent at $3–10 per million tokens
- Claude Sonnet 5.5 vs Muse WonderFastest with similar intelligence
- Claude Sonnet 5.5 vs Claude Fable 5.1Just above overall
- Claude Sonnet 5.5 vs Muse Spark 1.3Just below overall
- GPT-6.1 Terra vs Claude Opus 5.5Highest-scoring overall available today
- GPT-6.1 Terra vs GPT-6.1 SolJust below overall
Quick answers
Is Claude Sonnet 5.5 better than GPT-6.1 Terra?
Pick GPT-6.1 Terra: it scores higher (Spring Prompt overall 83 against 63) and costs less.
Which is cheaper, Claude Sonnet 5.5 or GPT-6.1 Terra?
GPT-6.1 Terra is cheaper to run: $0.004 against $0.017 per product listing on CatalogBench (4.8 times less).
Which is better for product listings, Claude Sonnet 5.5 or GPT-6.1 Terra?
GPT-6.1 Terra ranks 4 of 27 models on sale for turning a sparse product feed and photos into listings that can go live, against 14 for Claude Sonnet 5.5.
Which is better for decks from an analysis, Claude Sonnet 5.5 or GPT-6.1 Terra?
Claude Sonnet 5.5 ranks 5 of 28 models on sale for turning a finished analysis into a deck you could present as it is, against 6 for GPT-6.1 Terra.
Which is better for marketing planning, Claude Sonnet 5.5 or GPT-6.1 Terra?
GPT-6.1 Terra ranks 1 of 28 models on sale for planning a year of ad spend without overspending, against 6 for Claude Sonnet 5.5.
Which is better for speed under pressure, Claude Sonnet 5.5 or GPT-6.1 Terra?
GPT-6.1 Terra ranks 16 of 31 models on sale for good decisions against a real clock (fast chess), against 28 for Claude Sonnet 5.5.
Which has the bigger context window, Claude Sonnet 5.5 or GPT-6.1 Terra?
GPT-6.1 Terra: 1,050,000 tokens, against 1,000,000 for Claude Sonnet 5.5.
Run Claude Sonnet 5.5 and GPT-6.1 Terra on your own prompt
Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.