Terra
gpt-5.6-terra
- Input
- $2.00
- Cached
- $0.20
- Output
- $12.00
OpenAI model family / GPT-5.6 Access checked · August 6, 2026
Sol Terra Luna
GPT-5.6 access depends on the product surface.
Free and Go move to Luna with an announced unlimited-text and Think rollout; Plus and Pro get an updated ChatGPT-only Sol with a thought slider. Work, Codex, the API, and Flowith remain separate version or access checks.
API price record · July 30, 2026
Terra and Luna cost less
These are OpenAI's Standard API rates per 1 million tokens for short-context requests. Prompts above 272K input tokens, other processing modes, cache writes, tools, data residency, and third-party platforms can use different rates.
Luna
gpt-5.6-luna
- Input
- $0.20
- Cached
- $0.02
- Output
- $1.20
API token prices are separate from ChatGPT Work and Codex subscriptions. OpenAI says subscription prices and quota budgets stayed unchanged, while Terra and Luna now consume fewer credits on paid subscriptions.
Family map
Choose by operating role
The tier names are durable roles. Exact limits, pricing, and features should always be checked in the live OpenAI docs.
S Flagship capability
Sol
gpt-5.6-sol
Complex production work where quality, coding, knowledge work, and difficult multi-step execution matter most.
T Balanced everyday work
Terra
gpt-5.6-terra
Strong general performance when a workflow needs a lower-cost role than the flagship tier.
L Fast, efficient throughput
Luna
gpt-5.6-luna
High-volume or latency-sensitive work where efficiency is the primary model-selection constraint.
Sol processing choice
Standard, Fast, and a limited Ultrafast preview
Fast is the documented premium processing mode for ordinary API requests. Ultrafast is a separate selected-customer Sol API preview powered by Cerebras; its provider-reported output rate is not an end-to-end latency, price, SLA, or access guarantee.
Standard
Default choice when cost matters more than premium latency.
No Fast mode opt-in required.
Use as the evaluation baseline for latency and completed-task cost.
Fast
High-value, user-facing Sol work where latency is worth a premium.
Set service_tier to "fast"; "priority" remains compatible.
Up to 2.5× faster for Sol at twice the Standard token price; ramp limits can downgrade traffic.
Ultrafast preview
Selected-customer Sol API work where output speed is the defining constraint.
No public request parameter documented in the announcement.
Provider-reported up to 750 output tokens/s and up to 14× Standard; price, SLA, fallback, regions, and broader availability are not stated.
Requests using the legacy priority value continue to work. Fast traffic can be downgraded to Standard when ramp-rate limits apply; inspect the returned service tier and usage data when latency or billing matters.
The Ultrafast announcement does not document a public request value. Do not infer one from the Fast API or present the preview as available in Codex, ChatGPT, Flowith, or third-party providers.
Availability boundary
One name, separate access contracts
The August 6 announcement changes ChatGPT access and controls; it does not update Work or Codex Sol, define a new API revision, or establish a Flowith launch, entitlement, free-credit offer, or model mapping.
Surface What official evidence supports Flowith interpretation
ChatGPT Free and Go
Luna becomes the default during the August 6 rollout week. Unlimited text and a Think button begin the following week, subject to abuse guardrails; uploads, images, and other tools retain limits.
ChatGPT plan access only; not evidence of Flowith access.
ChatGPT Plus and Pro
The updated ChatGPT-only Sol powers quick and deeper responses. A slider on web, mobile, and desktop controls how much thought ChatGPT applies.
A ChatGPT control, not an API or Flowith setting.
Work
OpenAI says the Sol version powering Work did not change in the August 6 ChatGPT release.
Separate OpenAI product and version boundary.
Codex
OpenAI says the Sol version powering Codex did not change in the August 6 ChatGPT release.
Separate OpenAI product and version boundary.
OpenAI API
OpenAI documents Sol, Terra, and Luna model IDs. Ultrafast for Sol is a limited preview for selected API customers, not general API availability.
Does not confirm a Flowith model mapping.
Flowith
No internal launch evidence was found for GPT-5.6 during this route review.
Verify in the live workspace model selector.
Selection protocol
Three checks before you switch
Choose the tier by role
Start with Sol for frontier capability, Terra for balanced work, or Luna for efficient throughput. Do not collapse a multi-model workflow into one tier without evaluation.
Confirm the product surface
ChatGPT, Codex, the OpenAI API, and Flowith have separate access and entitlement boundaries. Verify the surface you will actually use.
Choose the processing mode
Use Standard as the baseline. Test documented Fast mode when latency is worth the premium. Treat Ultrafast as a separate selected-customer preview until access, request, pricing, and operating terms are documented for your account.
Test the real contract
Measure task success, output completeness, latency, token use, tools, and structured-output behavior on representative work before switching.
Primary sources
Read the live OpenAI record
Use the announcement for the availability event and the model guide for current implementation details.
August 6 ChatGPT update Official Luna access, unlimited-text and Think rollout, Plus and Pro thought slider, and the Work/Codex version boundary. GPT-5.6 launch announcement OpenAI's July 9, 2026 release, family tiers, product availability, and launch-level capability summary. GPT-5.6 model guidance Current API model identifiers, workload roles, reasoning settings, feature notes, and migration guidance. July 30 price update Official Terra and Luna price changes, paid-product credit implications, and the Sol Fast mode announcement. OpenAI API pricing Live Standard, Batch, Flex, Fast, cached-input, and long-context token rates for the GPT-5.6 family. Fast mode guide Current request parameters, Priority Processing compatibility, billing, ramp-rate behavior, and regional caveats. Ultrafast preview announcement Selected-customer GPT-5.6 Sol API preview, provider-reported output speed, Cerebras infrastructure, and capacity-bound expansion.
Related model routes
GPT-5.2 Review the former flagship's documented variants and a safe migration handoff to the current family. DeepSeek V4 Compare another coding and long-context route while keeping provider and Flowith access boundaries separate. Gemini 3.1 Compare a Google model route when the task depends on a different multimodal or provider boundary. Grok 4 Review another reasoning route when live-answer style analysis is a core workflow requirement.
GPT-5.6 questions, answered
GPT-5.6 is OpenAI's model family launched for general availability on July 9, 2026. The family includes Sol, Terra, and Luna tiers for different capability, cost, and throughput roles.
Sol is the flagship tier, Terra is the balanced lower-cost tier, and Luna is the fastest and most affordable tier. Choose by workload requirements rather than treating the family as one interchangeable model.
OpenAI documents gpt-5.6-sol, gpt-5.6-terra, and gpt-5.6-luna. The gpt-5.6 alias routes to gpt-5.6-sol according to the current model guidance.
For Standard API processing with short context, OpenAI lists Terra at $2 per million input tokens, $0.20 cached input, and $12 output. Luna is $0.20 input, $0.02 cached input, and $1.20 output. Long-context, Batch, Flex, Fast, regional, tool, and cache-write charges can differ, so verify the live pricing table before budgeting.
No subscription price change was announced in the July 30 update. OpenAI says ChatGPT and Codex subscription prices and quota budgets remain unchanged, while Terra and Luna use fewer credits on paid subscriptions. Your actual allowance still depends on the live product, plan, and account terms.
OpenAI renamed Priority Processing to Fast mode on July 30, 2026. For GPT-5.6 Sol, OpenAI says Fast mode can be up to 2.5 times faster than Standard at twice the token price. API requests using either the fast or legacy priority service-tier value remain supported, but regional availability and ramp-rate behavior still need verification.
No. OpenAI announced Ultrafast on August 13, 2026 as a limited preview for selected API customers. It reports up to 750 output tokens per second and up to 14 times Standard speed, but the announcement does not publish a price, SLA, request parameter, fallback rule, regional matrix, or availability in ChatGPT, Codex, Flowith, or Amazon Bedrock.
OpenAI documents GPT-5.6 across ChatGPT, Work, Codex, and the API, but the access contract differs by product. In the August 6 ChatGPT update, Luna becomes the Free and Go default; Plus and Pro receive an updated ChatGPT-only Sol and thought slider; the Sol versions powering Work and Codex do not change. None of those provider surfaces automatically establishes availability inside Flowith.
OpenAI announced Luna as the Free and Go default during the week of August 6, 2026, followed the next week by unlimited text chats and a Think button. The unlimited-text access remains subject to abuse guardrails, and separate limits still apply to uploads, images, and other tools. Check the live ChatGPT account because rollout timing and entitlements can vary.
No. OpenAI says the August 6 Sol update is optimized for the Chat experience in ChatGPT. The Sol version powering Work and Codex did not change as part of that release.
This page does not claim that GPT-5.6 is currently available on Flowith. Check the live Flowith workspace model selector and account entitlements before planning a workflow.
Test a migration on representative tasks first. Preserve the endpoint, tools, output contract, reasoning behavior, latency role, and cost role before adopting new GPT-5.6 features.
Start with Sol when quality is the priority, Terra for a balanced everyday role, and Luna for efficient high-volume work. Validate the choice against your own task-success, latency, and cost requirements.