iNaturalist is a nonprofit online community for naturalists, citizen scientists, and biologists. It is based on the idea of mapping and sharing observations of living things around the world. People can use iNaturalist through its website or mobile apps. The platform includes a tool that helps identify species automatically, and users also help each other by sharing photos and sound recordings to identify plants, animals, fungi, and other organisms. As of August 5, 2025, iNaturalist users had shared nearly 300 million observations of living things worldwide, and 400,000 users were active in the past 30 days.

iNaturalist provides free data that helps scientists, conservationists, and educators study and protect biodiversity. It describes itself as "an online social network of people sharing biodiversity information to help each other learn about nature." It is widely used in countries such as Mexico, southern Africa, and Australia to collect data from many people. Most of its software is open source, meaning others can use and improve it. iNaturalist has helped create over 4,000 research papers and is used globally by scientists, land managers, and conservationists. The platform has also helped discover new species and find species that were once thought to be extinct.

History

iNaturalist started in 2008 as a final project by Nate Agrin, Jessica Kline, and Ken-ichi Ueda, who were students in the Master's program at the UC Berkeley School of Information. Agrin and Ueda continued developing the site with Sean McGregor, a web developer. In 2011, Ueda worked with Scott Loarie, a research fellow at Stanford University and lecturer at UC Berkeley. Ueda and Loarie are now the joint leaders of iNaturalist.org. The organization merged with the California Academy of Sciences on April 24, 2014. In 2017, iNaturalist became a shared project between the California Academy of Sciences and the National Geographic Society.

Because of these partnerships and the site's growing popularity since 2012, the number of users and observations has roughly doubled each year. In 2014, iNaturalist reached 1 million observations. As of October 2023, there were 181 million observations, with 163 million confirmed as accurate. On July 11, 2023, iNaturalist announced it had become an independent nonprofit organization.

In June 2025, Google announced that iNaturalist would join its "Generative AI Accelerator." This news, combined with limited details on the iNaturalist website, caused many users to express concern in blog comments and forums. People worried about the impact on the environment, volunteer involvement, and the reliability of the site. Some users questioned the decision-making process at iNaturalist, while others viewed the reaction as a sign of resistance to "corrosive technologies." PZ Myers, a biology professor who uses iNaturalist in his teaching, wrote an article on his website, Pharyngula, stating, "any decision that drives people away and replaces them with a hallucinating bot is a bad decision."

Platforms

People can use iNaturalist in these ways:

• through the iNaturalist.org website,
• through two mobile apps: iNaturalist (for iOS and Android devices) and Seek by iNaturalist (for iOS and Android devices), or
• through partner organizations, such as the Global Biodiversity Information Facility (GBIF) website.

On the iNaturalist.org website, visitors can search a public database of observations and communicate with others who add or identify species. Registered users can upload observations, identify species, write about their findings in journals, learn about different species, create project pages to invite others to join, and work together on topics they care about.

The iNaturalist mobile app allows users to record and share nature observations with the online database. It also lets users explore observations near them or around the world and learn about different types of plants and animals.

Seek by iNaturalist is a separate app designed for families. It does not require users to create an online account, and observations can stay private. The app includes game-like features, such as showing a list of nearby organisms to find, earning badges, and joining challenges. Seek was first released in the spring of 2018.

Observations

The iNaturalist platform uses information shared by people to record and identify living things. An iNaturalist observation shows when and where a person sees a specific organism. It can also include signs of an organism, like animal tracks, nests, or scat. The platform does not record non-living natural features, such as rocks or rivers. Most users upload photos to support their observations, though audio recordings are also allowed. Sharing location details is optional, with choices to show exact locations, less precise locations, or keep them private.

Users can help identify each other’s observations to improve accuracy. Observations are labeled as "Casual," "Needs ID," or "Research Grade" based on the quality of the data and community input. All data from iNaturalist can be downloaded, and "Research Grade" observations are often used in other scientific databases, like the Global Biodiversity Information Facility and the Atlas of Living Australia.

In addition to community help, iNaturalist has an automated tool to identify species. This tool, introduced in 2017, uses a computer model trained on the large collection of images on iNaturalist. It provides multiple species suggestions, with the most likely one listed first. If the model is unsure, it may suggest a broader group, like a genus or family. The model is updated once or twice each year, and the types of species included have changed over time. The tool may struggle to identify rare species, organisms hard to recognize from pictures, or images with poor lighting, blurriness, or multiple subjects.

In February 2023, iNaturalist released version 2.1 of its computer model, which performed better than earlier versions. In April 2025, the iOS app was updated, and the original version was renamed "iNaturalist Classic."

Projects

Users have created and contributed to tens of thousands of different projects on iNaturalist. The platform is often used to record observations during bioblitzes, which are events where people try to find and record all the species in a specific area as part of a project on iNaturalist. Other project types include collecting observations based on location or taxon, or documenting specific types of observations such as animal tracks, signs, invasive species, roadkill, fishing catches, or new species. In 2011, iNaturalist was used to support the Global Amphibian and Global Reptile BioBlitzes. Observations from these events helped scientists track the locations and numbers of reptile and amphibian species worldwide. The US National Park Service worked with iNaturalist to record observations during the 2016 National Parks BioBlitz. That project had more than 100,000 observations in August 2016. In 2017, the United Nations Environment Programme partnered with iNaturalist to celebrate World Environment Day. In 2022, Reef Ecologic partnered with iNaturalist to celebrate World Oceans Day.

In 2016, Lila Higgins from the Natural History Museum of Los Angeles County and Alison Young from the California Academy of Sciences started the City Nature Challenge (CNC). During the first CNC, naturalists in Los Angeles and the San Francisco Bay Area recorded over 20,000 observations using iNaturalist. In 2017, the CNC expanded to 16 cities in the United States, where people collected over 125,000 wildlife observations in 5 days. In 2018, the CNC became a global event with 68 cities in 19 countries participating. Some cities used other community science platforms, but over 17,000 people recorded more than 440,000 nature observations in urban areas around the world in 4 days. In 2019, the CNC grew to include 159 cities with 35,000 participants who collected 964,000 observations of over 31,000 species. In 2020, the CNC had fewer observations due to the COVID-19 pandemic, but more cities and people joined, and more species were found than in previous years.

Licensing

Users can choose how to license their observations, photos, and audio recordings. Options include public domain, Creative Commons, or all rights reserved. To help share information and save costs, iNaturalist suggests using Creative Commons licenses. The default license is CC BY-NC, which allows others to copy, share, change, or use the media in new ways as long as they give proper credit, show changes made, include a link to the license, and do not use it for money.

Media with Creative Commons licenses are often shared on other platforms, such as the Global Biodiversity Information Facility (except for licenses that require sharing back or no changes), the Atlas of Living Australia, and Wikipedia (except for licenses that restrict commercial use or changes). These platforms use tools like iNaturalist2Commons and Wiki Loves iNaturalist to import or share content.

The iNaturalist website and mobile apps are open-source software, meaning others can use and improve them. This software is released under the MIT License.

Research

As of January 2024, more than 4,000 research papers have used data from iNaturalist, which shares observations with the Global Biodiversity Information Facility (GBIF). These papers often focus on topics like ecology, conservation, and climate change. Many studies examine how climate changes affect where species live. For example:

• In 2015, iNaturalist data showed that the Hopkin's rose nudibranch (Ceratodoris rosacea) is moving to the north.
• In 2022, photos on iNaturalist confirmed that the New Zealand hermit crab (Pagurus traversi) was found in Tasmania and Victoria, Australia.
• In February 2024, photos from iNaturalist were used to report that hermit crabs are using artificial shells, such as plastic bottle caps.
• In April 2024, iNaturalist data showed that Himalayan giant honey bees (Apis laboriosa) have expanded their range to Thailand for the first time.

iNaturalist data has also been used to study phenology, which is the study of how living things change with the seasons.

A 2023 study compared iNaturalist lichen records with expert identifications in Portugal and Italy. It found that fewer than half of the species reported by iNaturalist users matched expert findings, and about 70% of species-level identifications on iNaturalist were incorrect. The study suggested that unverified observations, especially for hard-to-identify groups like lichens, should be used carefully in research. It also recommended raising the standards for "research-grade" observations and providing clearer guidelines for volunteers. A 2024 review of lichen conservation practices warned that iNaturalist records are often hard to confirm from photos alone and should usually be excluded from conservation assessments unless species can be clearly identified or verified by experts.

Other research has focused on discovering new species or finding species thought to be extinct. For example:

• A snail species, Myxostoma petiverianum, not seen since 1905, was found in Vietnam based on a photo uploaded to iNaturalist in 2014.
• In 2013, a citizen scientist in Colombia uploaded a photo of a poison dart frog, which was identified as a new species, Andinobates cassidyhornae.
• In 2023, a mantis species discovered with help from iNaturalist was named Inimia nat, a name that honors iNaturalist.
• The first wild photo of the New Britain goshawk was shared on iNaturalist in March 2024. The Colombian weasel, one of the rarest neotropical carnivores, was seen for the first time in the 21st century when an iNaturalist user uploaded photos of the animal.
• Two teenagers in California used iNaturalist observations of unfamiliar scorpions to help describe two new species (Paruroctonus soda and Paruroctonus conclusus).
• The frosted phoenix moth of New Zealand, thought to be extinct, was rediscovered when a Swedish birder took a photo of the insect and uploaded it to iNaturalist. This was the first sighting in 65 years.
• A commuter in London uploaded a photo of an insect on her bag to iNaturalist, which was identified as a plane lace bug, Corythucha ciliata. This was the first recorded sighting in the UK in about 18 years and led to a national monitoring effort.
• In December 2024, a new population of critically endangered Canterbury knobbled weevils (Hadramphus tuberculatus) was discovered after a farmer in New Zealand uploaded a photo of weevils found on a plant.
• A presumed extinct Australian plant, Ptilotus senarius, was confirmed to be alive and rare based on an iNaturalist observation in June 2025.

Other research has studied the physical features or colors of species. For example, a 2019 study examined how wing coloration in dragonflies (Pachydiplax longipennis) relates to temperature.

Mycologists who run community labs for fungal DNA barcoding published 45,000 DNA sequences between 2016 and 2023, many through iNaturalist. iNaturalist allows users to link photos and location data with DNA sequences. Using iNaturalist helps experts and amateur mycologists review and share findings. As of December 2025, more than 7,600 fungi species on iNaturalist had DNA barcodes. In December 2025, iNaturalist introduced a "provisional name" field in a pilot program. This allows experts to label DNA-barcoded fungi that may be new species with temporary names, such as Calonarius sp. 'CA03'. Similar temporary names are used for plant galls that have not been formally described, like q-montana-fuzzy-sphere-cluster for fuzzy galls on chestnut oak leaves.

Graphs

• A graph that shows changes each year in how many species were seen (measured in thousands; shown in green) and how many confirmed observations were made (measured in millions; shown in black).
• The share of confirmed observations by category of living things as of January 2022.