How to Edit a Video With AI Using Text Prompts - Free (2026)

TL;DR

• Go to Magic Hour's AI Video Editor: Upload a video and start editing without creating an account or downloading software.
• Upload and describe the change: Add your clip, then type a specific instruction such as “Remove the car in the background” or “Change the sky to a sunset.”
• Generate with AI: Magic Hour applies the prompt to your footage and gives you an edited version to review and refine.
• Free vs. paid: The free editor gives you 3 edits per day, with each free generation limited to 3 seconds at 480p and a Magic Hour logo. Paid users can choose additional models: Google Omni supports 3–10 second edits at 720p, while LTX-2.3 supports 0.5–45 second edits at 1080p. 

Intro

Traditional video editing can turn a simple visual change into a tedious process of cutting, masking, tracking, and adjusting individual elements. Prompt-based editing works differently: you type what you want changed, and AI applies that instruction to the footage without a traditional timeline. This guide shows how to edit a video with AI in your browser using Magic Hour's AI Video Editor.

Timeline Editing vs Prompt-Based Editing

If you need a traditional editor for cutting clips and assembling a complete video, CapCut or VEED is the better fit. If the footage is already shot and you mainly want to change what appears inside the frame, prompt-based editing is usually faster.

What You Can Edit With a Text Prompt

• Remove an object: Tell the AI to erase a distracting person, car, logo, prop, or other background element.
• Replace a background: Describe a new setting, such as changing an indoor room into a studio, beach, or city street.
• Restyle footage: Turn ordinary footage into an anime, cinematic, watercolor, claymation, fantasy, or cyberpunk look.
• Change a color: Specify the object and its new color, such as changing a car, clothing item, or foliage to blue or pink.
• Add atmosphere: Ask for rain, fog, sunset light, birds, or another environmental effect.
• Enhance lighting: Ask the AI to brighten a dark scene, improve lighting on the subject, or make the footage look cleaner and more polished.

What You Need Before You Start

• A video clip: For the best results, keep your source video under 45 seconds. The available generation length depends on the model you choose.
• A modern web browser: Magic Hour's AI Video Editor runs directly in your browser, so there is no software to download.
• No account required: You can use the free editor without signing up.
• Three free edits per day: Free users get 3 generations per day, with each free generation limited to 3 seconds at 480p. Paid users can select models with longer generation limits.

Comparison Table

Magic Hour is the clearest match if the requirement is prompt-based video editing with no sign-up, while Descript, Kapwing, and Runway are broader editing platforms that require an account for their free tiers. Runway's free tier currently provides 125 one-time credits and adds a watermark to generated videos; Kapwing's free exports also carry a watermark, while Descript's free plan allows limited 720p watermark-free exports.

How to Edit a Video With AI: Step by Step

Step 1: Go to Magic Hour's Free AI Video Editor

Open the Magic Hour AI Video Editor. The product page lets you upload a video and describe the change you want without creating an account or downloading an application.

Step 2: Upload Your Video

Click the upload area and add the clip you want to change. For the free workflow, keep the source footage short because the free generation is limited to a 3-second edited result; stable framing, clear subjects, and consistent lighting are also better starting points for AI edits.

Step 3: Type Your Edit Prompt

Enter your instruction in the prompt field under the video upload. The strongest prompts identify what to change, where it is, and what you want instead rather than simply saying “make it better.”

For example, a prompt that specifies the target element and what should remain unchanged gives the AI clearer instructions. 

Step 4: Choose Your Model (Paid Users Only)

Free users do not need to choose a model. The free workflow automatically uses the available free configuration and limits each generation to 3 seconds.

Paid users can choose between different models depending on the length and quality they need. Google Omni supports 3–10 second edits at 720p, while LTX-2.3 supports 0.5–45 second edits at 1080p.

Step 5: Generate

Click Generate Video or the edit/generate button after entering your prompt. Magic Hour then applies the instruction to the uploaded footage rather than asking you to manually mask or manipulate the object on a timeline.

Step 6: Review and Download

Watch the result carefully before using it. If the object was only partially removed, the replacement looks inconsistent, or the style is too strong, adjust the prompt and generate another variation; Magic Hour's workflow is designed around reviewing the result and refining the instruction.

Prompts That Actually Work

Prompt specificity makes a noticeable difference when editing video with AI. Instead of describing a general goal, specify the element to change, where it appears, what you want it changed to, and which parts of the scene should remain untouched.

Edit type: Remove

Prompt used: “Remove the person walking in the background on the right side of the frame. Keep the main subject, camera movement, and background scenery unchanged.”

What it produced: The background person was removed while the main subject remained in place, although the area where the person had been was slightly softer than the surrounding background.

Why it works: The prompt identifies the exact person to remove and explicitly tells the model which important parts of the footage to preserve.

Edit type: Replace

Prompt used: “Remove the ‘ON AIR’ text from the illuminated sign in the background and replace it with ‘Magic Hour’. Keep the same sign shape, position, size, lighting, glow, perspective, and background. Make ‘Magic Hour’ look naturally integrated into the existing illuminated sign. Do not change the cat, headphones, microphone, coffee cup, camera framing, or overall scene.”

What it produced: The sign was changed from “ON AIR” to “Magic Hour” while the cat, microphone, headphones, and rest of the scene remained largely unchanged.

Why it works: It gives the model a specific replacement target and adds preservation instructions for the surrounding scene instead of simply asking it to “change the text.”

Edit type: Restyle

Prompt used: “Restyle the entire scene as a cinematic animated film. Keep the cat, headphones, microphone, coffee cup, and composition recognizable, but give the scene a polished animated look with soft cinematic lighting.”

What it produced: The footage took on a more stylized animated appearance while retaining the basic composition and recognizable elements of the original shot.

Why it works: The prompt combines a clear style direction with instructions to preserve the key subjects and composition.

Edit type: Change color

Prompt used: “Change the color of the illuminated ‘Magic Hour’ sign in the background from its current color to deep blue. Keep the text, sign shape, glow, brightness, and everything else in the scene unchanged.”

What it produced: The sign shifted toward blue while the rest of the scene retained its original appearance.

Why it works: Specifying both the target object and the exact property to change reduces the chance that the model will reinterpret unrelated parts of the frame.

Edit type: Add atmosphere

Prompt used: “Add a subtle layer of warm morning fog around the background and window area. Keep the cat, microphone, headphones, coffee cup, and foreground sharp and unchanged. Make the fog look natural and softly illuminated by the existing light.”

What it produced: A light atmospheric haze appeared in the background while the foreground remained relatively clear.

Why it works: The prompt defines where the effect should appear and where it should not, which helps prevent the atmospheric effect from covering the main subject.

Edit type: Enhance lighting

Prompt used: “Improve the lighting on the cat's face and fur. Make the subject slightly brighter and more cinematic while preserving the original colors, background, headphones, microphone, and camera framing.”

What it produced: The cat became brighter and more visually prominent without requiring changes to the composition.

Why it works: The prompt limits the enhancement to the subject and specifies that the original colors and surrounding elements should remain intact.

Prompts That Did Not Work Well

Not every prompt needs to be long to work, but vague instructions can give the model too much room to reinterpret the scene.

Prompt: “Make it better.”

What happened: The result changed the overall appearance without a clear, predictable improvement to a specific part of the video.

Why it failed: There was no defined target, visual change, or preservation instruction for the model to follow.

Prompt: “Remove everything in the background.”

What happened: The model treated too much of the background as part of the requested removal, making the scene look less natural.

Why it failed: The instruction was too broad and did not distinguish between the unwanted element and background details that should remain.

Prompt: “Make the cat look cooler.”

What happened: The result introduced stylistic changes to the cat rather than making one clearly defined visual adjustment.

Why it failed: “Cooler” is subjective and does not tell the model whether to change the lighting, color, expression, fur, accessories, or overall style.

The pattern is simple: prompts work better when they describe one specific change, identify where it should happen, and explain what should stay unchanged. For short AI video edits, that level of specificity gives the model a much narrower target to work with.

What to Try Next

If the edited clip is too short, use Magic Hour's AI Video Extender to generate additional footage that continues the original scene.
If you need the same footage in another format, use Magic Hour's AI Video Expander to change the aspect ratio without simply cropping the original frame.
Both follow the same basic idea: upload existing footage, choose the AI operation you need, generate the result, and download it.

Frequently Asked Questions

Is it free?

Yes. Magic Hour's AI Video Editor gives free users 3 generations per day, with each generation limited to 3 seconds at 480p and a Magic Hour logo. Paid users get access to additional models, including Google Omni for 3–10 second edits and LTX-2.3 for 0.5–45 second edits, with higher-resolution output. 

How is this different from CapCut or VEED?

Magic Hour's AI Video Editor is not a traditional timeline editor: you upload footage and describe the visual change you want, rather than trimming clips, arranging multiple tracks, or dragging effects onto a timeline. CapCut and VEED are better choices when you need to assemble a complete video, while Magic Hour is better suited to changing elements inside an existing short clip.

What edits can I make with a prompt?

You can remove objects or people, replace backgrounds or scene elements, add objects and effects, change colors and lighting, restyle footage, and create creative variations from existing clips. Magic Hour specifically lists object removal, background replacement, additions, visual-detail changes, restyling, and enhancement among the editor's supported use cases.

How long does generation take?

Most edits process in 30 to 90 seconds, depending on clip length and current server load. Free users are limited to 3-second edits, while paid users can access longer durations through models such as LTX-2.3, which supports 0.5–25 seconds at up to 1080p. 

Can I use the output commercially?

Not on the free tier. Magic Hour states that paid plans permit commercial use, while free users can preview and test generated content for personal, non-commercial purposes; the current Creator plan starts at $12/month when billed annually and includes commercial use and watermark-free exports.