How accurate is Free Plant Identifier?
Tests last run
How often does it name the right plant?
Free Plant Identifier names the right plant first time 88.3% of the time and has it in its top five 96.6% of the time, using where the photo was taken. We measured this on 3,880,456 real photos of 56,498 plants, as of November 2026.
| Measure | Photo only | With location |
|---|---|---|
| First pick is the right plant | 77.2% | 88.3% |
| Right plant is in the top five | 91.8% | 96.6% |
Does accuracy depend on the plant?
Yes. Plants with more photos on record are easier to name, so we report them separately.
| Plants | Plants tested | Test photos | First pick, with location | Top five, with location | First pick, photo only | Top five, photo only |
|---|---|---|---|---|---|---|
| Common: 1,000 or more photos on record | 10,673 | 3,565,492 | 89.0% | 96.9% | 77.5% | 91.9% |
| Uncommon: 100 to 999 photos on record | 25,744 | 263,293 | 84.7% | 96.2% | 77.6% | 93.2% |
| Rare: fewer than 100 photos on record | 20,081 | 51,671 | 59.0% | 84.2% | 49.6% | 77.8% |
How accurate is the weed identifier?
The weed identifier is 99.0% accurate. That score covers its firm yes or no answers about the state or country a photo was taken in. It says not sure on 6.1% of photos. Weeds get a yes 85.5% of the time, a no 2.6% and a not sure the rest. Other plants get a no 95.3% of the time and a yes 0.4%.
| Where the photos were taken | Test photos | Accuracy | Firm answers given | Weeds said yes to | Other plants said no to |
|---|---|---|---|---|---|
| Every country with a list | 72,879,938 | 99.0% | 93.9% | 85.5% | 95.3% |
| United States | 33,359,025 | 98.9% | 93.1% | 86.6% | 94.2% |
| Outside the United States | 39,520,913 | 99.0% | 94.6% | 84.4% | 96.2% |
| Russia | 6,806,843 | 98.7% | 93.8% | 74.3% | 95.9% |
| Canada | 6,751,391 | 98.9% | 92.9% | 87.6% | 93.8% |
| Australia | 2,762,922 | 99.3% | 95.9% | 86.9% | 97.8% |
| United Kingdom | 2,698,577 | 98.9% | 92.9% | 89.0% | 93.5% |
| South Africa | 1,958,464 | 99.0% | 96.3% | 75.9% | 97.9% |
| Germany | 1,740,918 | 99.1% | 94.0% | 85.1% | 95.4% |
| France | 1,572,592 | 99.4% | 96.0% | 85.0% | 97.2% |
| Spain | 1,497,835 | 99.1% | 95.9% | 84.2% | 97.3% |
| New Zealand | 1,445,088 | 98.3% | 94.5% | 75.8% | 96.6% |
| Mexico | 1,280,048 | 99.8% | 99.3% | 88.1% | 99.5% |
| Austria | 1,194,250 | 98.8% | 93.2% | 76.5% | 95.4% |
| Italy | 1,005,504 | 99.4% | 95.9% | 85.9% | 97.1% |
| Ukraine | 833,157 | 98.5% | 91.1% | 80.6% | 92.9% |
| Portugal | 677,808 | 99.1% | 95.9% | 86.3% | 97.5% |
| Czechia | 669,478 | 98.9% | 91.6% | 85.2% | 92.7% |
How were these numbers measured?
The photos. Every test photo is a confirmed sighting from iNaturalist, kept out of the build. 5% of photographers were set aside completely, so nearly all the test photos come from people whose photos the identifier has never seen.
The test. The identifier ranks all 60,902 plants for each photo. First pick counts when its top match is the plant the sighting was confirmed as, and top five counts when that plant is among its first five matches.
Location. With location, matches are re-ranked using iNaturalist records near where the photo was taken. The setting for how much location counts was chosen on 362,867 other photos, not the ones reported here.
Weeds. A plant counts as a weed in a place when a law, an official invasive list or a recognised weed guide names it for that state or country. We hold 917 lists across the US, Canada, Europe and Australia, and use the Global Register of Introduced and Invasive Species elsewhere, as of November 2026. A firm answer means at least 80% sure either way.
Can I check the raw results?
Yes. These are the files the tables on this page come from.