Runway Gen-4.5 Overview | ImagineArt

For quite some time, Sora 2 and Veo 3.1 dominated the AI video generation world and for all the right reasons. Then came a whispering thunder ‘David’ that surpassed all the video models on Artificial Analysis Leaderboard with an Elo score of 1247. The reigning model remained unknown until Runway ML came with a release: the Gen-4.5.

What is Runway Gen-4.5?

Runway AI collaborated with NVIDIA to create the latest Gen-4.5 model. The AI video generator is built using Autoregressive-to-Diffusion (A2D) techniques and NVIDIA GPUs to improve pre- and post-data training efficiency and techniques. The A2D blends the visual fidelity of diffusion models and the language and scene understanding of an autoregressive model into one core system.

In simpler words, your characters won’t morph or disappear behind objects, the visuals are sharper, and the physics simulation is errorless. This Runway AI model will remember the objects and characters as they are, without altering anything. Permanence, speed, temporal consistency — this isn’t just an upgrade, this is a category all of its own.

Introducing our new frontier video model, Runway Gen-4.5. Previously known as Whisper Thunder (aka) David.

Gen-4.5 is state-of-the-art and sets a new standard for video generation motion quality, prompt adherence and visual fidelity.

Learn more below. pic.twitter.com/2J945S4bQt

— Runway (@runwayml) December 1, 2025

Core Features of Runway Gen-4.5

Runway unveiled the Gen-4.5 video generator.

They've improved physics and object detail. In Artificial Analysis's user rankings, the model has surpassed Veo 3.1 and Sora 2 Pro.

Access will be rolled out gradually throughout this week.https://t.co/ITobcOZc2h pic.twitter.com/aTWcFbfVYs

— shields 👽 (@ImMrShields) December 2, 2025

Runway Gen-4.5 is packed with incredible features, setting new standards in consistency, controllability, and performance.

1. Improved Physics Simulation

Runway Gen-4.5 has a comprehensive understanding of the physical state, movement, momentum, weight, fluidity, and dynamics of objects and their surroundings. With Gen-4.5, you can create realistic movements and motion dynamics with visual precision.

For instance, a wave crashing at the shore ebbs away gradually instead of vanishing completely from sight. The AI video generator understands the cause-and-effect relationship of motion and maintains the sequence of actions.

2. Strong Prompt Adherence

This Runway text-to-video model takes prompt adherence up a notch, rendering surface-level details with greater fidelity. The AI ensures the subtleties of elements and characters remain true to their form without losing any realism. The finer texture of skin or fabric, how hair strands respond to the wind, the ripples in water, or realistic shadow and reflections — every minute detail is retained and made believable.

3. Expressions and Emotions

Creating realistic characters has always been the hallmark of Runway ML video generation AI models. With Gen-4.5, you can build characters with realistic facial details, lifelike authenticity, and emotional depth. The AI video model accurately captures the micro-expressions, emotional nuances, and feelings. The emotions won’t be reflected through the change in expressions only, but also the often-elusive change in body language. The rapid eye blinking to fight back the tears, the slight tilt of the head to express disagreement, the deliberate frown to indicate annoyance — your characters will be more relatable and alive.

4. Multi-Element Scenes

Runway Gen-4.5 can seamlessly handle the intricacies of layered visual elements, ensuring consistency and coherence. The AI video generator preserves every detail, environmental factors, movements, interactions, and shifts in conditions to render realistic results. With Runway Gen-4.5, you can create scenes with a certain sense of space, realistic dimensions, and visual depth.

5. Multi-Style Support

Runway Gen-4.5 comes with stylistic flexibility, including photorealism, cinematic, stylized visuals, animations, and more. The AI video model excels at replicating realism, adding depth of field for cinematic outputs, and incorporating vivid aesthetics or animations. From dramatic compositions to immersive lifelike experiences, Gen-4.5 offers a dynamic blend of aesthetics without losing fidelity or consistency.

Runway Gen-4.5 vs. Veo 3 & Sora 2

Google’s SOTA models Veo 3 suffered a 20-point defeat in the Artificial Analysis Leaderboard, with Veo 3.1 in fourth position and OpenAI’s Sora 2 at seventh position. The reasons can be manifold:

• Native Audio Support

Unlike Google Veo 3 and Veo 3.1, Runway doesn’t have native audio support. It can be a dealbreaker for those looking for a quick video creation process sans the audio editing. At this point, Google Veo 3 and Veo 3.1 might win with ease of use and convenience. However, Runway Gen-4.5 is fully capable of winning over the professional creators with its visual fidelity and prompt adherence — the blind test and Elo scores on Artificial Analysis are proof of it.

• Stylistic Control

Runway Gen-4.5 offers extensive style diversity with thorough temporal coherence. Even though Veo 3, Veo 3.1, and Sora 2 also feature stylistic diversity, they lack temporal coherence. Often, the objects flicker, characters change appearance, and scenes transition awkwardly.

• Real-time Editing

Unlike Google Veo 3, Veo 3.1, Sora 2 storyboard, Runway Gen-4.5 doesn’t have built-in video editing features. But you can edit video using Runway Alpeh on the same platform.

• Video Length

This new Runway AI model is optimized for creating short-form content of up to 10 seconds, especially for YouTube, TikTok, Reels, and short films. Whereas with Veo 3.1, you can extend the video length to a minute, letting you create comparatively longer videos. Sora 2 also allows you to create videos of up to 25 seconds.

Use Cases for Runway Gen-4.5

• Content Creators

Enter your content details as a prompt, and let Runway text-to-video generation AI model create stories, ads, and brand videos for your social media platforms without any need for editing. Perfect for creating dance videos and fitness content, where body movements, trajectories, and motion dynamics are important.

• Marketing

With Runway Gen-4.5, brand and marketing professionals can create compelling product ads, demo videos, promotional materials, marketing explainer videos, and opening or closing shots for product ads quite efficiently.

• Filmmaking

Create cinematic scenes rich with realistic emotions, expressions, and action sequences. Perfect for storyboarding, creating trailers, animation projects, and short films.

• Gaming Content

Gaming enthusiasts and developers can generate in-game cinematics, animated scenes, trailers, gameplay teasers, and character or feature showcases.

Limitations of Runway Gen-4.5

According to Runway ML, the model still has a few limitations:

• Runway Gen-4.5 has exhibited glitches in physics understanding. In some videos, action happened after the consequence.
• Object permanence is the Achilles’ heel of AI video generation, and Runway ML is working to perfect it. You might notice sudden disappearances of objects in various frames.
• The AI video model can sometimes overestimate the correctness and accuracy of an action, leading to incorrect results.

Pricing of Runway Gen-4.5

Runway Gen-4.5 is available for all subscription plans on Runway ML:

• The free access comes with 125 one-time credits with no Gen-4 access.
• The standard plan costs around $12/user/month with 625 monthly credits.
• The pro plan costs around $28/user/month with 2250 monthly credits.
• The unlimited plan costs around $76/user/month with 2250 monthly credits and unlimited generations.

Recommended read: Runway AI Pricing: Free vs Paid Plans

Conclusion

Runway AI new model had a major breakthrough with temporal coherence and physical plausibility. Though it has its own limitations, Runway Gen-4.5 might just become the go-to AI video generator for short-form content.

In case you are looking for an all-in-one AI video creation and editing experience, try Kling O1 and Kling 2.6 on ImagineArt AI video generator.

For a recap of previous Runway AI video models, read: Runway AI Overview