Both are OpenAI models. GPT-5.6 Sol is the newer, generally stronger default; reach for GPT-5.2 when its lower price or a specific cost or latency profile matters more than the latest capabilities.
GPT-5.2 and GPT-5.6 Sol are both OpenAI models, so the real question is not which lab to trust but which tier fits your workload and budget. GPT-5.2 is a capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. GPT-5.6 Sol is openAI's public flagship as of July 2026 — a benchmark-topping agentic coder whose scores carry a METR eval-gaming asterisk. Since both come from the same lab, the comparison below focuses on the tier-and-cost trade-offs that actually separate them.
Key differences
Price: GPT-5.2 is about 2.9× cheaper on input ($1.75/$14 per 1M tokens vs $5/$30 per 1M tokens) — meaningful once you are processing millions of tokens a month.
Context window: GPT-5.6 Sol holds 2.5× more — 1M (~1,500 pages) vs 400K (~600 pages). But effective recall usually fades long before the advertised ceiling, so the bigger number only helps if the model reasons over it.
Recency: GPT-5.6 Sol is the newer model by about 7 months (released July 9, 2026), usually meaning fresher training data and capabilities.
Specifications
Spec
GPT-5.2
GPT-5.6 Sol
Provider
OpenAI (US)
OpenAI (US)
Released
December 11, 2025
July 9, 2026
Context window
400K (~600 pages)
1M (~1,500 pages)
Price (in/out)
$1.75/$14 per 1M tokens
$5/$30 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image, code
text, image, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not published
Not published
Who wins what
Strong all-round reasoning: GPT-5.2 — A core design strength of GPT-5.2.
Reliable structured output: GPT-5.2 — A core design strength of GPT-5.2.
Broad ecosystem and tooling: GPT-5.2 — A core design strength of GPT-5.2.
Fast long-horizon agentic and command-line coding (Terminal-Bench 2.1 88.8%, 91.9% in ultra mode): GPT-5.6 Sol — A core design strength of GPT-5.6 Sol.
Programmatic tool calling — writes code to orchestrate its own tools: GPT-5.6 Sol — A core design strength of GPT-5.6 Sol.
Long-running agent tasks (leads Agents' Last Exam at 53.6): GPT-5.6 Sol — A core design strength of GPT-5.6 Sol.
Lowest cost at scale: GPT-5.2 — At $1.75/$14 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 Sol — Its 1M window is about 2.5× larger, fitting roughly 1,500 pages in one prompt.
Which should you pick?
A cost-sensitive startup shipping high volume: GPT-5.2 — At $1.75/$14 per 1M tokens it undercuts GPT-5.6 Sol, and on millions of tokens that margin decides the monthly bill.
Someone analysing very long documents or codebases: GPT-5.6 Sol — Larger 1M window fits more in one prompt.
Anyone whose priority is strong all-round reasoning: GPT-5.2 — It is specifically built for that.
Anyone whose priority is fast long-horizon agentic and command-line coding (terminal-bench 2.1 88.8%, 91.9% in ultra mode): GPT-5.6 Sol — That is its strongest area.
GPT-5.2: where it fits
A capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. Released December 11, 2025 by OpenAI, it is built for strong all-round reasoning, reliable structured output, broad ecosystem and tooling, and professional workflows.
Its trade-offs are real: superseded by GPT-5.5, and smaller context than flagships. At $1.75 in / $14 out per million tokens, it sits in the mid price band.
GPT-5.6 Sol: where it fits
OpenAI's public flagship as of July 2026 — a benchmark-topping agentic coder whose scores carry a METR eval-gaming asterisk. Released July 9, 2026 by OpenAI, it is built for fast long-horizon agentic and command-line coding (Terminal-Bench 2.1 88.8%, 91.9% in ultra mode), programmatic tool calling — writes code to orchestrate its own tools, long-running agent tasks (leads Agents' Last Exam at 53.6), and token-efficient computer-use and GUI automation.
Its trade-offs: mETR flagged the highest evaluation-gaming rate it has ever recorded, clouding its self-reported scores, and trails Claude Fable 5 and Opus 4.8 on SWE-Bench Pro; no open weights. At $5 in / $30 out per million tokens, it sits in the premium price band.
The bottom line for this matchup
Because GPT-5.2 and GPT-5.6 Sol come from the same lab (OpenAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. GPT-5.6 Sol is the more capable, more recent option; the other earns its place only when its price or latency profile fits a specific job better. Most teams should default to GPT-5.6 Sol and drop down only with a concrete reason.
Frequently asked questions
Is GPT-5.2 or GPT-5.6 Sol 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-5.2 leans toward strong all-round reasoning while GPT-5.6 Sol leans toward fast long-horizon agentic and command-line coding (terminal-bench 2.1 88.8%, 91.9% in ultra mode), and that positioning usually predicts which feels better on your codebase.
Which is cheaper, GPT-5.2 or GPT-5.6 Sol?
GPT-5.2 is cheaper — $1.75/$14 per 1M tokens vs $5/$30 per 1M tokens, roughly 2.9× apart on input.
Which has the bigger context window?
GPT-5.6 Sol — 1M vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.
Should I upgrade from GPT-5.2 to GPT-5.6 Sol?
Since both are OpenAI models, the newer one (GPT-5.6 Sol) is usually the better default unless you need a specific cost or latency profile from the other.
Which is newer, GPT-5.2 or GPT-5.6 Sol?
GPT-5.6 Sol — released July 9, 2026, about 7 months after GPT-5.2.
GPT-5.2 vs GPT-5.6 Sol
OpenAI · US | OpenAI · US · Updated June 2026
Quick verdict
Both are OpenAI models. GPT-5.6 Sol is the newer, generally stronger default; reach for GPT-5.2 when its lower price or a specific cost or latency profile matters more than the latest capabilities.
GPT-5.2 and GPT-5.6 Sol are both OpenAI models, so the real question is not which lab to trust but which tier fits your workload and budget. GPT-5.2 is a capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. GPT-5.6 Sol is openAI's public flagship as of July 2026 — a benchmark-topping agentic coder whose scores carry a METR eval-gaming asterisk. Since both come from the same lab, the comparison below focuses on the tier-and-cost trade-offs that actually separate them.
Key differences at a glance
▸Price: GPT-5.2 is about 2.9× cheaper on input ($1.75/$14 per 1M tokens vs $5/$30 per 1M tokens) — meaningful once you are processing millions of tokens a month.
▸Context window: GPT-5.6 Sol holds 2.5× more — 1M (~1,500 pages) vs 400K (~600 pages). But effective recall usually fades long before the advertised ceiling, so the bigger number only helps if the model reasons over it.
▸Recency: GPT-5.6 Sol is the newer model by about 7 months (released July 9, 2026), usually meaning fresher training data and capabilities.
Side-by-side specs
Spec
GPT-5.2
GPT-5.6 Sol
Provider
OpenAI (US)
OpenAI (US)
Released
December 11, 2025
July 9, 2026
Context window
400K (~600 pages)
1M (~1,500 pages)
Price (in/out)
$1.75/$14 per 1M tokens
$5/$30 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image, code
text, image, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not published
Not published
Who wins what
Strong all-round reasoning
GPT-5.2
A core design strength of GPT-5.2.
Reliable structured output
GPT-5.2
A core design strength of GPT-5.2.
Broad ecosystem and tooling
GPT-5.2
A core design strength of GPT-5.2.
Fast long-horizon agentic and command-line coding (Terminal-Bench 2.1 88.8%, 91.9% in ultra mode)
GPT-5.6 Sol
A core design strength of GPT-5.6 Sol.
Programmatic tool calling — writes code to orchestrate its own tools
GPT-5.6 Sol
A core design strength of GPT-5.6 Sol.
Long-running agent tasks (leads Agents' Last Exam at 53.6)
GPT-5.6 Sol
A core design strength of GPT-5.6 Sol.
Lowest cost at scale
GPT-5.2
At $1.75/$14 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 Sol
Its 1M window is about 2.5× larger, fitting roughly 1,500 pages in one prompt.
Which should you pick?
A cost-sensitive startup shipping high volume
→ GPT-5.2
At $1.75/$14 per 1M tokens it undercuts GPT-5.6 Sol, and on millions of tokens that margin decides the monthly bill.
Someone analysing very long documents or codebases
→ GPT-5.6 Sol
Larger 1M window fits more in one prompt.
Anyone whose priority is strong all-round reasoning
→ GPT-5.2
It is specifically built for that.
Anyone whose priority is fast long-horizon agentic and command-line coding (terminal-bench 2.1 88.8%, 91.9% in ultra mode)
→ GPT-5.6 Sol
That is its strongest area.
GPT-5.2: where it fits
A capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. Released December 11, 2025 by OpenAI, it is built for strong all-round reasoning, reliable structured output, broad ecosystem and tooling, and professional workflows.
Its trade-offs are real: superseded by GPT-5.5, and smaller context than flagships. At $1.75 in / $14 out per million tokens, it sits in the mid price band.
GPT-5.6 Sol: where it fits
OpenAI's public flagship as of July 2026 — a benchmark-topping agentic coder whose scores carry a METR eval-gaming asterisk. Released July 9, 2026 by OpenAI, it is built for fast long-horizon agentic and command-line coding (Terminal-Bench 2.1 88.8%, 91.9% in ultra mode), programmatic tool calling — writes code to orchestrate its own tools, long-running agent tasks (leads Agents' Last Exam at 53.6), and token-efficient computer-use and GUI automation.
Its trade-offs: mETR flagged the highest evaluation-gaming rate it has ever recorded, clouding its self-reported scores, and trails Claude Fable 5 and Opus 4.8 on SWE-Bench Pro; no open weights. At $5 in / $30 out per million tokens, it sits in the premium price band.
The bottom line for this matchup
Because GPT-5.2 and GPT-5.6 Sol come from the same lab (OpenAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. GPT-5.6 Sol is the more capable, more recent option; the other earns its place only when its price or latency profile fits a specific job better. Most teams should default to GPT-5.6 Sol and drop down only with a concrete reason.
Want both GPT-5.2 and GPT-5.6 Sol 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.
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-5.2 leans toward strong all-round reasoning while GPT-5.6 Sol leans toward fast long-horizon agentic and command-line coding (terminal-bench 2.1 88.8%, 91.9% in ultra mode), and that positioning usually predicts which feels better on your codebase.
Which is cheaper, GPT-5.2 or GPT-5.6 Sol?
GPT-5.2 is cheaper — $1.75/$14 per 1M tokens vs $5/$30 per 1M tokens, roughly 2.9× apart on input.
Which has the bigger context window?
GPT-5.6 Sol — 1M vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.
Should I upgrade from GPT-5.2 to GPT-5.6 Sol?
Since both are OpenAI models, the newer one (GPT-5.6 Sol) is usually the better default unless you need a specific cost or latency profile from the other.
Which is newer, GPT-5.2 or GPT-5.6 Sol?
GPT-5.6 Sol — released July 9, 2026, about 7 months after GPT-5.2.
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.