GPT-5.6 Terra vs Grok 4.7

OpenAI · US  |  xAI · US · Updated June 2026

Quick verdict

Pick GPT-5.6 Terra for balanced everyday work at roughly half of sol's price or competitive with gpt-5.5 quality at about 2x lower cost. Pick Grok 4.7 for 2.1 trillion parameters, up 40% from grok 4.6's 1.5 trillion, at the same $2/$6 per million token price or deepswe v1.1 (high effort): 71.0%, up from grok 4.6's 65.2%; cursorbench 4.0: 46.3%, up from 40.4%. On a tight budget at scale, Grok 4.7 is the value pick.

GPT-5.6 Terra (OpenAI) and Grok 4.7 (xAI) are two of the models people most often weigh against each other in 2026. GPT-5.6 Terra is the mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost. Grok 4.7 is xAI's September 21, 2026 update — a 2.1T-parameter model trained partly on SpaceX hardware data, same price as Grok 4.6 but stronger on coding benchmarks. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecGPT-5.6 TerraGrok 4.7
ProviderOpenAI (US) xAI (US)
ReleasedJuly 9, 2026 September 21, 2026
Context window1M (~1,500 pages) 500K tokens (~750 pages)
Price (in/out)$2.5/$15 per 1M tokens $2/$6 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Balanced everyday work at roughly half of Sol's price

GPT-5.6 Terra

The mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost — and it carries the larger 1M context.

Competitive with GPT-5.5 quality at about 2x lower cost

GPT-5.6 Terra

GPT-5.6 Terra lists competitive with GPT-5.5 quality at about 2x lower cost among its strengths; Grok 4.7 does not.

Solid agentic coding (Terminal-Bench 2.1 in the mid-80s)

GPT-5.6 Terra

GPT-5.6 Terra lists solid agentic coding (Terminal-Bench 2.1 in the mid-80s) among its strengths; Grok 4.7 does not.

2.1 trillion parameters, up 40% from Grok 4.6's 1.5 trillion, at the same $2/$6 per million token price

Grok 4.7

At $2/$6 per 1M tokens it undercuts GPT-5.6 Terra ($2.5/$15 per 1M tokens), and that gap compounds at volume.

DeepSWE v1.1 (high effort): 71.0%, up from Grok 4.6's 65.2%; CursorBench 4.0: 46.3%, up from 40.4%

Grok 4.7

XAI's September 21, 2026 update — a 2.1T-parameter model trained partly on SpaceX hardware data, same price as Grok 4.6 but stronger on coding benchmarks — and it runs cheaper at $2/$6 per 1M tokens.

Trained with supplemental SpaceX data (Starlink telemetry, manufacturing records, engineering failure logs) — xAI says this improves reasoning about hardware and physical systems

Grok 4.7

XAI's September 21, 2026 update — a 2.1T-parameter model trained partly on SpaceX hardware data, same price as Grok 4.6 but stronger on coding benchmarks — and it is the newer of the two.

Lowest cost at scale

Grok 4.7

At $2/$6 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

GPT-5.6 Terra

Its 1M window is about 2× larger than Grok 4.7's 500K tokens, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Grok 4.7

At $2/$6 per 1M tokens it undercuts GPT-5.6 Terra, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

GPT-5.6 Terra

Larger 1M window fits more in one prompt.

Anyone whose priority is balanced everyday work at roughly half of sol's price

GPT-5.6 Terra

It is specifically built for that.

Anyone whose priority is 2.1 trillion parameters, up 40% from grok 4.6's 1.5 trillion, at the same $2/$6 per million token price

Grok 4.7

That is its strongest area.

GPT-5.6 Terra: where it fits

The mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost. Released July 9, 2026 by OpenAI, it is built for balanced everyday work at roughly half of Sol's price, competitive with GPT-5.5 quality at about 2x lower cost, solid agentic coding (Terminal-Bench 2.1 in the mid-80s), and same 1M context and programmatic tool calling as Sol.

Its trade-offs are real: fewer independently verified benchmarks than Sol, and trails it across coding evals, and no open weights. At $2.5 in / $15 out per million tokens, it sits in the mid price band.

Grok 4.7: where it fits

XAI's September 21, 2026 update — a 2.1T-parameter model trained partly on SpaceX hardware data, same price as Grok 4.6 but stronger on coding benchmarks. Released September 21, 2026 by xAI, it is built for 2.1 trillion parameters, up 40% from Grok 4.6's 1.5 trillion, at the same $2/$6 per million token price, deepSWE v1.1 (high effort): 71.0%, up from Grok 4.6's 65.2%; CursorBench 4.0: 46.3%, up from 40.4%, trained with supplemental SpaceX data (Starlink telemetry, manufacturing records, engineering failure logs) — xAI says this improves reasoning about hardware and physical systems, and xAI's strongest safety guardrails to date, per the company.

Its trade-offs: release was delayed at least five times since late July 2026 before shipping, 500K context window trails several rivals now sitting at 1M+, and reviewers note it arrives "late to the AI frontier party" against GPT-6 Astra, Claude Fable 5.1 and Opus 5.5, all shipped in the weeks just before it. At $2 in / $6 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

GPT-5.6 Terra and Grok 4.7 overlap enough that the right pick depends on your specific job. Grok 4.7 costs less per token; GPT-5.6 Terra holds the larger context; and each leads in its own area — GPT-5.6 Terra for balanced everyday work at roughly half of sol's price, Grok 4.7 for 2.1 trillion parameters, up 40% from grok 4.6's 1.5 trillion, at the same $2/$6 per million token price. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both GPT-5.6 Terra and Grok 4.7 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is GPT-5.6 Terra or Grok 4.7 better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, GPT-5.6 Terra leans toward balanced everyday work at roughly half of sol's price while Grok 4.7 leans toward 2.1 trillion parameters, up 40% from grok 4.6's 1.5 trillion, at the same $2/$6 per million token price, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-5.6 Terra or Grok 4.7?

Grok 4.7 is cheaper — $2.5/$15 per 1M tokens vs $2/$6 per 1M tokens, roughly 1.3× apart on input.

Which has the bigger context window?

GPT-5.6 Terra — 1M vs 500K tokens, about 2× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both GPT-5.6 Terra and Grok 4.7 together?

Yes — a multi-model platform like LumiChats gives you GPT-5.6 Terra, Grok 4.7 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, GPT-5.6 Terra or Grok 4.7?

Grok 4.7 — released September 21, 2026, about 2 months after GPT-5.6 Terra.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.