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The best climate analysis tools for architects

Climate analysis turns a site's sun, wind, temperature and humidity into design decisions. These are the tools architects use for it, what each does well, and what it needs from you.

Last checked18 September 2026

At a glance

ToolTypePriceBest for
CBE Clima ToolWeb app, open sourceFreeA free, thorough analysis of a weather station's EPW file in the browser, for early design and teaching.
Ladybug ToolsPlugins for Grasshopper (Rhino), open sourceFree and open source; requires Rhino (a commercial Rhino 8 licence is US$995 in North America)Parametric climate and comfort studies linked to your own Rhino geometry.
C4BWeb appFree plan; paid plans from €59/month (cancellation takes effect after 12 billing cycles) or €599/year, with a 7-day free trialA complete site climate brief from an address, including site-specific data, future climate and a first energy balance.
Climate ConsultantDesktop app (Windows, macOS)FreeLearning to read a climate and the classic passive design strategies on a psychrometric chart.
EPW InsightsWeb app, open source (AGPL-3.0)FreeA free, private way to explore an EPW file in depth, including a first look at future climate.
Forma Site DesignCloud softwareStandalone subscription or part of the AEC Collection; 30-day free trialTesting massing options against sun, daylight, wind, noise and outdoor comfort on a real site model.
ClimateStudioRhino plugin (Windows)Price on requestPractices that want climate, daylight and energy simulation in one Rhino plugin.
DesignBuilder Climate AnalyticsWeb app€895/year, including 150 download creditsEnergy modellers who need weather files for many locations, including actual years and future projections.
Weather Data and Psychrometric Chart web appsWeb appsFreeQuick, interactive visualisations of an EPW file for teaching and presentations.

How to choose

Start with the data. Most tools analyse an EPW weather file: a typical year for a weather station, usually from Climate.OneBuilding.Org or the EnergyPlus library. That works well when the station is close to the site and similar to it. When the nearest station is far away, on the coast or at a different altitude, look for a tool that can use data at the site itself, or be ready to source a better file.

Then match the tool to how you work. Browser apps need nothing installed and suit early briefs, teaching and quick checks. Rhino plugins such as Ladybug Tools and ClimateStudio link the analysis to your own geometry, which pays off once there is a design to test, but they assume Rhino, and for Ladybug some Grasshopper skill. Model-based cloud tools such as Forma Site Design analyse massing options on a site rather than the climate record itself.

Check what you need to hand on. Some tools export chart graphics and CSV data, some produce a written report, and some only show results on screen. If the analysis will feed an energy model later, check whether you can download the weather file itself.

Finally, think about the building's lifetime. A typical year describes the recent past. If overheating, comfort or cooling loads decades ahead matter to the brief, choose a tool with future climate scenarios, or pair your analysis tool with a future weather file generator.

CBE Clima Tool

Center for the Built Environment (CBE), UC Berkeley · Web app, open source · Free

A free, thorough analysis of a weather station's EPW file in the browser, for early design and teaching.

  • A map of EPW files for more than 27,500 locations from EnergyPlus and Climate.OneBuilding.Org, or upload your own EPW.
  • Sun path, wind rose, psychrometric chart, natural ventilation potential, UTCI outdoor comfort and degree days.
  • Charts download as SVG and the underlying data as CSV.
  • Open source, and described in a peer-reviewed paper in Building Simulation (online 2023; vol. 17, 2024).

Good to know

  • It analyses the EPW you choose or upload; future climate is not among the tabs listed in its documentation.

Visit CBE Clima Tool

Ladybug Tools

Ladybug Tools LLC · Plugins for Grasshopper (Rhino), open source · Free and open source; requires Rhino (a commercial Rhino 8 licence is US$995 in North America)

Parametric climate and comfort studies linked to your own Rhino geometry.

  • Imports EPW files, and can find and download them with its EPWmap and Download Weather components.
  • Components for sun path, wind rose and psychrometric chart, and for UTCI, PMV and adaptive comfort.
  • Honeybee, from the same team, connects the model to energy and daylight simulation engines.

Good to know

  • Runs inside Rhino and Grasshopper, so it assumes a Rhino licence and some visual-scripting experience.

Visit Ladybug Tools

C4B

We make C4B

Embrace Ideas · Web app · Free plan; paid plans from €59/month (cancellation takes effect after 12 billing cycles) or €599/year, with a 7-day free trial

A complete site climate brief from an address, including site-specific data, future climate and a first energy balance.

  • Starts from an address or a point on the map and analyses the nearest OneBuilding.org station file (usually TMYx); projects on paid plans add a typical year compiled from ERA5 / ERA5-Land, CERRA or NORA3 reanalysis at the site's coordinates, corrected to its elevation.
  • Köppen-Geiger and ASHRAE 169 climate zones, wind roses, sun path, psychrometric chart, UTCI outdoor comfort, precipitation, solar radiation and PV potential.
  • Future climate under five SSP scenarios for any year from 2025 to 2100, in projects on paid plans.
  • Written readings on most charts in projects, and a PDF report on paid plans.

Good to know

  • Site-specific data is at reanalysis grid-cell resolution (kilometres), not microclimate; there is no daylight simulation or CFD, and no CSV or JSON data export.
  • EPW downloads are only available on the Technical and Enterprise plans.

Climate Consultant

UCLA Energy Design Tools Group (distributed by SBSE) · Desktop app (Windows, macOS) · Free

Learning to read a climate and the classic passive design strategies on a psychrometric chart.

  • Reads annual 8,760-hour EPW weather files.
  • Dozens of graphic displays, including the psychrometric chart and the wind wheel.
  • Its psychrometric chart shows the share of hours in 16 design strategy zones and generates a list of design guidelines for the location.

Good to know

  • Latest Windows build listed: 6.0 Build 17 (October 2021); latest macOS build: 6.0 Build 13 (January 2020). The download page states it will not run on macOS Ventura.

Visit Climate Consultant

EPW Insights

Ehsan Rostami · Web app, open source (AGPL-3.0) · Free

A free, private way to explore an EPW file in depth, including a first look at future climate.

  • Runs entirely in the browser: files are parsed locally and nothing is uploaded to a server.
  • Psychrometric chart with bioclimatic strategy overlays, UTCI and other outdoor comfort indices, wind rose, sun path, solar radiation and thermal mass analyses.
  • Future climate projections for 2030, 2050 and 2080 under four SSP scenarios using CMIP6 morphing, and side-by-side comparison of two files or scenarios.

Visit EPW Insights

Forma Site Design

Autodesk · Cloud software · Standalone subscription or part of the AEC Collection; 30-day free trial

Testing massing options against sun, daylight, wind, noise and outdoor comfort on a real site model.

  • Sun hours, daylight potential, wind, microclimate (outdoor thermal comfort), noise and solar energy analyses on your massing model.
  • Carbon analysis alongside the environmental analyses: total carbon (embodied and operational) since August 2026, first for projects hosted in the US.
  • Works with Revit, Rhino and Dynamo; a proposal can be sent to Revit as a geolocated model.

Good to know

  • Analyses run on a site and massing model; the pages we reviewed do not name the weather data source.

Visit Forma Site Design

ClimateStudio

Solemma LLC · Rhino plugin (Windows) · Price on request

Practices that want climate, daylight and energy simulation in one Rhino plugin.

  • A searchable library of over 30,000 weather files, with visualisations of temperature, humidity, wind, radiation and UTCI on site.
  • Spatial thermal comfort maps, EnergyPlus-based energy modelling, and daylight and glare analysis.

Good to know

  • Windows only: its documentation states that it does not currently run on macOS.

Visit ClimateStudio

DesignBuilder Climate Analytics

DesignBuilder Software Ltd · Web app · €895/year, including 150 download credits

Energy modellers who need weather files for many locations, including actual years and future projections.

  • Data from over 43,000 weather stations, plus actual-year data from NASA's MERRA-2 reanalysis on a 0.5° by 0.625° grid.
  • Design Year and Actual Year files download in EPW format, with data visualisation and selection tools.
  • Future projections based on CMIP6 SSP scenarios and the earlier IPCC SRES scenarios.

Visit DesignBuilder Climate Analytics

Weather Data and Psychrometric Chart web apps

Dr Andrew Marsh · Web apps · Free

Quick, interactive visualisations of an EPW file for teaching and presentations.

  • Weather Data shows any EPW metric as an interactive 3D surface by day and hour: drag and drop the file to start.
  • Psychrometric Chart overlays comfort zones and the Givoni bioclimatic chart, shows how it relates to the Olgyay chart, and loads EPW files.
  • Companion 2D and 3D sun-path apps on the same site.

Good to know

  • App pages dated June 2017 (Weather Data) and October 2018 (Psychrometric Chart).

Visit Weather Data and Psychrometric Chart web apps

See your site's climate before design begins

Pin any location and get climate, comfort and preliminary energy insight your whole team can read. Start with a 7-day free trial, or book a 30-minute demo.

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Frequently asked questions

What is the best free climate analysis tool for architects?

For analysing a weather station's EPW file, CBE Clima Tool is free, open source and runs in the browser. Climate Consultant and EPW Insights are also free. Ladybug Tools is free too, but it runs inside Rhino and Grasshopper, and Rhino needs a paid licence.

What data do climate analysis tools use?

Most analyse EPW weather files: a typical meteorological year for a weather station, built from years of historical records. Two widely used free sources are Climate.OneBuilding.Org, with TMYx files for more than 17,000 locations, and the EnergyPlus weather library. Some tools also use reanalysis data, which estimates the weather on a regular grid, so they can describe places far from any station.

Do I need Rhino or Grasshopper for climate analysis?

No. CBE Clima Tool, EPW Insights, C4B and Andrew Marsh's apps run in a web browser, and Climate Consultant is a desktop app. Rhino-based tools such as Ladybug Tools and ClimateStudio become useful when you want to link the climate to your own geometry.

Which climate analysis tools include future climate?

Among the tools in this guide, C4B (in projects on paid plans), EPW Insights and DesignBuilder Climate Analytics include future climate projections. With tools that accept your own EPW, such as CBE Clima Tool or Ladybug Tools, you can also analyse a future weather file made with a separate generator.

Sources

We make C4B. Information about the other tools comes from their official websites and documentation, checked on 18 September 2026. Products and prices change, so check each vendor's site for the latest details. All product names belong to their respective owners.

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