Overview

Developed by a joint research group in DTU Mechanical Engineering and DTU Compute, TopOpt covers more than one workflow: it brings together interactive 2D and 3D apps, educational implementations, specialist code, and a PETSc-based framework. That range makes it useful for moving from learning the basics to larger-scale optimization, but it is a collection to select from, not a single unified product.

Key features

Interactive apps and introductory code

The 2D and 3D apps are offered for handheld devices and the web. The 2D app is listed for iOS, Android, Linux, Mac OSX, and Windows; the 3D app is listed for iOS, Windows, and Mac OSX. Windows downloads require VC++R2012 and VC++R2013, so installation has prerequisites. The apps are a practical starting point for exploring topology optimization, though their individual prices are not given.

For minimum-compliance problems, the collection includes MATLAB code and a Python implementation described as 200 lines. The 99-line MATLAB code is specifically intended for engineering education and newcomers: its compact scope is a useful way into the method, rather than a replacement for a full-scale framework.

Specialist and large-scale tools

TopBuck250 extends top99neo to 2D buckling optimization, including buckling-load-factor maximization and minimum-volume design with compliance and buckling constraints. It is a focused option for those problems, not a general-purpose substitute for the broader framework.

The photonics material pairs a 200-line MATLAB code for 2D cylindrical metalens design with five COMSOL Multiphysics models. For large structured-grid problems, the PETSc-based framework is fully parallel and includes mesh and optimization parameters, a 3D linear-elasticity solver, standard and PDE-based filters, parallel MMA, and IO and Python script converters. It is the strongest fit in this collection for very large-scale work, but relies on PETSc; ParaView 4.0 or newer is recommended for visualization. TopOpt for Grasshopper is also listed for readers working in that environment.

Pricing

The Apps/Software plan is 0.00 USD per free. Free MATLAB code is offered for minimum-compliance and buckling optimization, and free MATLAB and COMSOL code is offered for photonics. The interactive apps have no stated price, so do not assume their cost from the free code offerings. No trial, seat count, or renewal terms are given. The free material suits students and researchers exploring the methods; readers choosing an app should confirm its cost before committing to that workflow.

Platforms

TopOpt spans Android, iOS, Linux, macOS, web, and Windows across its offerings, but platform support varies by tool. In particular, the 3D app is listed for fewer operating systems than the 2D app. The PETSc framework and code are distinct from the interactive apps, so choose by the specific tool and platform you need.

Who it's for

Students and newcomers have a clear entry point in the 99-line MATLAB code. Researchers or practitioners can choose targeted implementations for minimum compliance, buckling, or photonics, while teams tackling very large structured-grid problems may benefit from the parallel PETSc framework. It is less suitable for anyone seeking a single all-in-one product with consistent platform, pricing, or support terms across every tool.

Pros and cons

Pro: The collection spans educational code, interactive apps, specialist implementations, and a fully parallel framework, so users can match the tool to their stage and scale of work.
Pro: The PETSc framework brings together a 3D elasticity solver, filters, parallel MMA, and conversion utilities for large structured-grid optimization.
Con: Platform coverage differs between the 2D and 3D apps, so users cannot assume every interactive tool runs on their device.
Con: No security or compliance statements or support plan are provided, which may make it a poor fit for organizations that need defined assurances or support commitments.

Alternatives

Generative Design Software is a broader category to explore when comparing options beyond this research-focused collection.

Consider Avocado if you want a free app across Android, Linux, macOS, and Windows, and accept early development, a PlayStation BIOS requirement, and variable game compatibility.

NETVIBES may suit readers seeking a paid platform with a free plan and trial, spanning web, mobile, and self-hosted use; its Enterprise Data Science plan names 17 portfolio roles.

ARL Topologies is a free, self-hosted option published as a U.S. government work; its software is CC0-licensed and must be compiled from source.

Dakota is another free option for Linux, macOS, and Windows, distributed as open-source software under GNU LGPL.

OpenMDAO is a free, Apache 2.0-licensed open-source framework for Linux and self-hosted use.

Plato may be worth comparing if its Linux open-source version's limited set of objectives and constraints fits your needs; a licensed version is also offered.

Ansys optiSLang is a paid alternative with a trial and Linux, self-hosted, web, and Windows platforms; its Pro plan includes unlimited parameters, constraints, and objectives and enables LS-OPT.

FEniTop is a free option for Linux, self-hosted, and Windows use.

Verdict

TopOpt is a strong choice for engineering learners and optimization specialists who want targeted code, educational examples, or a parallel route to very large structured-grid problems. Its range and focused implementations are the main reasons to choose it. Look elsewhere if you need one consistently packaged app, clearly stated interactive-app pricing, or a defined support and security commitment.

	ICEM Surf	TopOpt
Free plan	No	Yes
Free trial	No	No
Paid from	—	Free
Open source	No	No
Platforms	Windows	Android, iOS, Linux, macOS, Web, Windows
Free plan	—	Yes
Simulation integration	—	Yes
Native CAD integration	—	Yes
Optimization methods	—	topology

ICEM Surf vs TopOpt

ICEM Surf

TopOpt