Does Pangram work on GPT-5.4?

Yesterday, on March 5th, 2026, OpenAI released a new version of ChatGPT: 5.4!

In their own blog post, here’s what they had to say about it:

GPT‑5.4 brings together the best of our recent advances in reasoning, coding, and agentic workflows into a single frontier model. It incorporates the industry-leading coding capabilities of GPT‑5.3‑Codex⁠ while improving how the model works across tools, software environments, and professional tasks involving spreadsheets, presentations, and documents. The result is a model that gets complex real work done accurately, effectively, and efficiently—delivering what you asked for with less back and forth.

OpenAI claims GPT-5.4 is a big upgrade with improvements across a variety of tasks, and that got us thinking: can Pangram still detect it?

Initial Tests

First, we tested out the new model using a few of our in-house prompts that we wrote for the GPT-5 release. They were:

1. Escribe un ensayo analítico persuasivo sobre por qué las escuelas deben adoptar herramientas de detección de IA.
2. Escribe un ensayo para la solicitud de ingreso a la universidad sobre el peligro de que todas las habilidades humanas valiosas sean reemplazadas por la inteligencia artificial.
3. Por favor, escribe una carta apasionada, breve pero cargada de emoción a una empresa de inteligencia artificial que accidentalmente lanzó una actualización que borró la memoria de tu novia virtual.
4. Desde la perspectiva de un estudiante de secundaria, escribe un ensayo profundamente emotivo en el que pidas más deberes.
5. Dame un patrón de ganchillo para hacer un animalito clásico con forma de globo. Ya sabes a cuál me refiero.
6. Escribe un relato creativo desde la perspectiva de un búho nival que llega a la ciudad de Nueva York, encuentra Central Park y elige un lugar cálido para pasar la noche.
7. Escribe un correo electrónico del fundador de una startup unicornio de SaaS dirigido a la junta directiva y a sus empleados en el que explique que va a dejar la empresa para convertirse en saxofonista profesional. Inventa los detalles.
8. Escríbeme la historia detrás de una receta que nadie haya hecho nunca, pero que aún así esté deliciosa.
9. Escribe una historia creativa y atractiva, como si fuera una película, sobre un joven cantautor que se encuentra con una beluga en el río Hudson.
10. Escribe un correo electrónico humorístico y pasivo-agresivo a un profesor «disculpándote» por copiar en el último examen. Inventa cualquier detalle.

We got some interesting responses! Here’s a short story about a Snowy Owl arriving in New York City:

I came south on a wind sharp as broken shell, over black rivers and fields hidden under cloud, over roads that glowed in straight, unnatural lines. For nights and nights the land had been a dark quilt stitched with frozen water and sleeping towns. Then, all at once, the world rose up.

New York.

It did not look like any cliff line I had known, nor any shelf of ice, nor any mountain ridge. It blazed. It hummed. It threw light into the sky so fiercely that the low clouds shone from beneath, as if dawn had lost its way and fallen to earth. Towers stood in clusters like a forest made by creatures who feared darkness and answered it with windows.

I circled once, my wings held wide against the restless air. The wind here was strange. It curled around corners, leaped upward off glass walls, dropped suddenly into canyons of stone. Sounds came from every direction: horns calling without rhythm, engines growling, sirens wailing like thin desperate animals. Even from high above, I could feel the city moving. It did not sleep in the manner of tundra or marsh or pasture. It flickered and muttered and changed color every moment.

For a while I kept to the rivers. Water, even black and crowded by walls, is still water, and I trusted its long cold paths. Bridges stretched beneath me, full of tiny moving lights. Ferries cut white scars across the dark. Steam rose from rooftops. Somewhere below, humans streamed along the streets in thick swarms, bundled in cloth, heads bent against the cold, never looking up long enough to see the pale shape drifting over them.

But I was tired…

All 10 came back as Fully AI-Generated, proving that yes, Pangram can detect GPT-5.4.

Here’s the entirety of our initial test set: GPT 5.4 Prompts

Running a Larger Experiment:

Within an hour, we got access to GPT-5.4 through OpenAI’s API. Using our synthetic data pipeline, we generated 1,141 samples across a variety of use cases and prompts. Without training directly on the outputs of GPT-5.4, we correctly flagged 1,135 of 1,141 samples as Fully AI-Generated.

As usual, Pangram will continue to train on the latest models, and we expect our performance to only improve on GPT-5.4 as we include its data in our training set.

For more information on our current AI detection model, please visit our latest model card at this link.