3D Model File Size Estimator: FBX, OBJ, glTF, STL, Blend & More

Want to know how big your 3D model will be before you hit export?

Whether you’re crafting game assets, prepping models for 3D printing, or optimizing AR/VR content, file size matters. Our 3D Model File Size Estimator gives you instant, accurate predictions, so that you can plan storage, avoid bloated exports, plan submission to clients, and deliver optimized assets with confidence.

About the Tool

The 3D Model File Size Estimator is your go-to companion for planning, optimizing, and managing the storage needs of your 3D assets. Whether you’re exporting for games, 3D printing, AR/VR, or film, this tool helps you:

• Estimate file sizes across multiple 3D formats (glTF, FBX, OBJ, STL, USDZ, and more)
• Understand texture memory impact based on resolution, map types, and quantity
• Preview optimization results, including compression savings and geometry reduction
• Compare real-world storage equivalents (e.g., “Your model = 2 minutes of 4K video”)

This tool is developed to estimate the 3D file size of your project. All you need is do is input some basic details of your project to estimate your 3D file size. 

It will help you save a lot of your time and effort by preventing future issues, such as failed uploads or slow transfer speeds. Our free 3D file size estimator tool helps you make informed decisions about your 3D projects, ensuring your work remains optimized and efficient. It will also help you plan your file uploads if the files are bigger.

How Does This 3D File Size Estimator Tool Work?

The tool itself might seem simple, but it is quite smart and computationally strong to provide you with the exact 3D file size of your project. We have developed it using complex logics, although it works completely on the front-end.

It consists of five important inputs:

• The type of your 3D model.
• The number of vertices or the little dots that make up your shape.
• The texture resolution – it’s what determines how sharp your images appear on the surface.
• The amount of textures, because an extra texture layer adds more data.
• The format in which you want to export your model.

When you input the above details, the tool applies common data averages to guess how much space your final file will consume. It provides you with a result in megabytes. This spares you from guessing, or exporting and sampling to see if it’s too large.

How to Use the Dropdowns and Input Fields in the Tool

Let’s break down each part of this tool. That way, you can see precisely what each of the settings is doing and how it will affect your final file size.

1. Select the Model Type

The first choice you will have available is a dropdown under the title Model Type. In this part, you will see various model types, and you can choose among them. Various types of models tend to offer various levels of detail.

The following model types are available:

1. Low-Poly (Game Asset): These models use tiny shapes and less number of points. They can be seen in many mobile games or applications that require a quick response. Files are usually small.
2. Mid Poly (Product Visualization): These you can use to display products on a website or an advert. They have sufficient detail to render realistically, but they are not on the scale of movie-quality models.
3. High Poly (Film Quality): These models are designed for movies and high-end video. They use very fine detail. This frequently results in substantially larger files.
4. Digital Sculpture: Because sculptures made in programs like ZBrush can be very detailed, with millions of tiny points. This model type creates the biggest file sizes.
5. Architectural Model: These represent buildings or rooms. The file size can be big, because they are built from many little details.

Select the one that most accurately reflects what you are building. This allows the tool to begin its estimate at a reasonable mean.

2. Enter the Vertex Count

Next, you’ll have to input the number of vertices. 

Vertices are very small points that shape your model. Think of them as little dots that, when connected, make the lines and surfaces of your 3D object. The more vertices you have, the smoother and detailed your model will be. Vertex can also increase your file size.

For example:

• A very basic model, like an action figure, might have only 1,000 vertices.
• So, a high-polygon game character could have about 50,000 vertices.
• A high-end sculpture for a movie might have 10 million vertices or more.

Tip for beginners: If you are unsure of your vertex count, you can open up your mesh in your 3D application or make a rough estimate and test again. 

3. Select the Texture Resolution

Textures are the images that map to the surface of your 3D Model. They provide a dash of color, patterns, and tiny details on surfaces. The resolution of the texture determines how clearly those parts can be seen.

This tool offers you some typical sizes of texture:

• 512 x 512 pixels: It is for very low details. Good for small background objects.
• 1024 x 1024 pixels: It is for relatively low details, but good for basic models.
• 2048 x 2048 pixels: It is for medium details. Frequently employed for primary items in games or shops.
• 4096 x 4096 pixels: It is for high details. Great for close-up in movies or on stage.
• 8192 x 8192 pixels: It is for extremely sharp details. Only to be used when the model will be viewed from very close.

The larger pixels you select, the larger your file size becomes. For instance, if the resolution is doubled, the file size is twice as large, not just once, but four times larger than the original. Make certain you choose the low to medium resolution to create a 3D file acceptable for your purposes.

4. Adjust the Number of Textures

Many 3D models have multiple textures. So you might have one texture for the color, a second for the little bumps (a normal map), and a third for how shiny the surface is (a specular map), for example.

The number of texture fields allows you to enter how many texture images your model uses overall. The book is your file, and each one of those adds more data to it. For example, if your model uses 5 textures, then it might be closer to roughly 5x larger than a model that uses only 1 texture.

By changing this value, you can experiment and see how much each additional layer will impact the estimated final file size.

5. Choose the File Format

Last, but not least, choose the format of the file you are going to make. This is significant since data is saved differently in different formats, which may affect the file size.

Here are short introductions of each format:

1. OBJ: A common pattern for preserving the shape. It is commonly used, but it can produce bigger files.
2. FBX: Saves shapes and textures, and in fact preserves animations. Popular in games and films. Since it contains more data, it typically results in larger files.
3. gITF: Designed for the web. It maintains all of that in one compact file. This is perfect for 3D files for faster loading on the web.
4. STL: Common for 3D printing. It saves only the shape, without colors or textures, making file sizes much smaller.
5. USD / USDZ: Created by Pixar. All of these formats include full scene, material, and lighting. For augmented reality (AR) on Apple devices, USDZ is particularly handy.
6. Blender (.blend): Saves your entire Blender project (scenes and settings). It is not intended for use other than the Blender software.
7. Maya (. ma/. mb) and 3ds Max (. max): Archive full scenes for Autodesk applications. Works best when everyone on your team uses the same software.

Since you are selecting the format that you will export, the tool could provide you with the closest file size approximation.

Disclaimer

We hope this tool will be of help to 3D modelers, game developers, VFX editors, or anybody else who finds it suitable for their work. We have tried to provide you with almost exact results, but there can be some ups and downs in the estimations. We are open for feedback on this tool, and you can get in touch with any enquiries.