biology

GPT-5.5

GPT-5.5 is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand GPT-5.5 rather than just read about it. In short: GPT-5.5 (Generative Pre-trained Transformer 5.5) is a large language model (LLM) released by OpenAI on April 23, 2026. The model is also known by its codename "Spud".

Key takeaways

GPT-5.5 belongs to biology; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect GPT-5.5 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of GPT-5.5 from memory before moving on to harder problems.

Reference excerpt

GPT-5.5 (Generative Pre-trained Transformer 5.5) is a large language model (LLM) released by OpenAI on April 23, 2026. The model is also known by its codename "Spud". OpenAI reported GPT-5.5 benchmark scores including 82.7% on Terminal-Bench 2.0, 51.7% on FrontierMath Tier 1–3, and 35.4% on FrontierMath Tier 4, while listing lower scores for Claude Opus 4.7 and Gemini 3.1 Pro on the same benchmarks. OpenAI said a recurring tendency in its models to mention goblins, gremlins, and other creatures began with GPT-5.1 and became noticeable in GPT-5.5's Codex testing. The company attributed the behavior to rewards used when training the "Nerdy" personality, which favored creature-word outputs and transferred beyond that personality during later training. OpenAI said it retired the Nerdy personality, removed the goblin-affine reward signal, filtered training data containing creature words, and added a developer-prompt instruction for GPT-5.5 in Codex. In April 2026, a GPT-5.5 developer-prompt instruction in the GitHub repository of Codex told it not to mention goblins if the user prompt did not require it. GPT-5.5-Cyber, along with Codex Security, was being used in June 2026 at the launch of the Patch the Planet project to help open-source projects find and fix vulnerabilities.

Release GPT-5.5 Thinking and GPT-5.5 Pro were released on April 23, 2026, with neither being available to free-tier users. OpenAI withheld API access at launch, saying that API deployments required "different safeguards"; GPT-5.5 and GPT-5.5 Pro became available in the API on April 24, 2026. GPT-5.5 Instant was released to free-tier users on May 5, 2026, replacing GPT-5.3 Instant as ChatGPT's default model for all users. On May 7, 2026, OpenAI announced GPT-5.5-Cyber, a limited-preview variant for vetted cybersecurity teams under its Trusted Access for Cyber program.

Reception ZDNET praised GPT-5.5 for its polished answers and "[s]trong performance across writing, coding, and reasoning tasks". Compared to its predecessor GPT-5.4, the website described GPT-5.5 as better, faster, and showing "improvements in agentic coding, conceptual clarity, scientific research ability, and accuracy during knowledge work". The AI Security Institute reported that GPT-5.5 had a 71.4% (±8.0%, one standard error) average pass rate on its expert-level cyber tasks, compared with 68.6% (±8.7%) for Anthropic's Claude Mythos Preview, and said GPT-5.5 "may be the strongest model we have tested" on that measure.

References

External links Official website

Illustrations

Worked examples

Example 1 — a first encounter with GPT-5.5

Start with the simplest possible case. Write down what GPT-5.5 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to GPT-5.5 before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about GPT-5.5 ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of GPT-5.5

In research: GPT-5.5 appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses GPT-5.5 in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: GPT-5.5 is common in secondary-school and first-year university syllabi. It links to neighbouring topics 2026 in artificial intelligence, 2026 software, ChatGPT, so understanding it makes those chapters shorter.
In everyday life: Look for GPT-5.5 outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “GPT-5.5” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study GPT-5.5 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what GPT-5.5 means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain GPT-5.5 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is GPT-5.5 in simple terms?

GPT-5.5 (Generative Pre-trained Transformer 5.5) is a large language model (LLM) released by OpenAI on April 23, 2026. The model is also known by its codename "Spud".

Why does GPT-5.5 matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study GPT-5.5?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on GPT-5.5.