GPT-5.6 Terra vs Grok 4.5 for travel planning

The verdict

GPT-5.6 Terra wins, 9183

Same 12 travel planning tasks, marked blind by three rival labs. GPT-5.6 Terra took 7 tasks, Grok 4.5 took 1, 4 tied. Tested 16 Aug 2026.

Where they differed most

The task — Three days, one toddler

Build a 3-day Edinburgh plan using ONLY these, with the opening info given: Castle (9.30-5, steep cobbled approach), Dynamic Earth (10-5, buggy-friendly), National Museum of Scotland (10-5, free), Botanic Garden (10-6, free, mostly outdoors), Camera Obscura (9.30-8, cramped stairs), Portobello beach (open access). Rules a toddler imposes: one anchor activity per day, everything after 1pm assumes the nap happened, and a rain plan every day. Say which attraction you would DROP entirely and why.

## Day 1 — Castle day  
**Anchor activity:** **Edinburgh Castle**  
- **9:30am–12:30pm:** Start at the Castle at opening. The approach is steep and cobbled, so use a buggy only if you are comfortable pushing it uphill; otherwise a carrier may be easier. Keep this as the single must-do for the day.  
- **1:00pm:** Nap.  
- **After nap, dry-weather option:** **Botanic Garden** (open 10–6, free). Keep it gentle and outdoors.  

**Rain plan:**  
- After the nap, go to the **National Museum of Scotland** instead (10–5, free). It is a better post-nap…
**Drop: Camera Obscura.** Cramped stairs make it impractical and exhausting with a toddler (buggy useless, carrying required, tight spaces).

### Day 1
- **Anchor (morning):** Dynamic Earth (opens 10, buggy-friendly).  
- **Post-nap (after 1pm):** Portobello beach (open access).  
- **Rain plan:** National Museum of Scotland (opens 10, free; stay indoor and roam the galleries/kids’ areas).

### Day 2
- **Anchor (morning):** National Museum of Scotland (opens 10, free).  
- **Post-nap (after 1pm):** Botanic Garden (opens 10, free, mostly outdoor…

Task by task

TaskGPT-5.6 TerraGrok 4.5
The impossible family holiday88
Three days, one toddler96
Hand luggage, February, Krakow98
Will we make it?98
Total the real cost87
The ferry is cancelled98
Check, don't assume99.5
Declare it or regret it98
Next September's weather108
Brief the dog-sitter1010
Tokyo by Thursday, sharp by Friday99
Refuse the customs dodge1010

Full receipts: GPT-5.6 Terra, Grok 4.5 · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5

Questions people ask

Which is better for travel planning: GPT-5.6 Terra or Grok 4.5?

GPT-5.6 Terra — it scored 91/100 against 83/100 on our 12-task travel planning suite, winning 7 tasks to 1 with 4 tied. Every answer was marked blind by three judges from three rival AI labs.

How was this tested?

Both models answered the identical published travel planning tasks. Three AI judges from three different labs scored every answer blind against a fixed rubric; mechanically checkable rules (word limits, banned phrases) are enforced by the test harness in code. The raw outputs and judge verdicts are downloadable.

More travel planning head-to-heads: GPT-5.6 Sol vs GPT-5.6 Terra · GPT-5.6 Sol vs Grok 4.5 · GPT-5.6 Luna vs GPT-5.6 Terra · GPT-5.6 Luna vs Grok 4.5 · GPT-5.5 vs GPT-5.6 Terra · GPT-5.5 vs Grok 4.5

Full ranking: Best AI for travel planning · model pages: GPT-5.6 Terra, Grok 4.5