LangSmith vs Weights & Biases:Which is more popular?
In September 2026, LangSmith had more branded searches than Weights & Biases among AI evaluation platforms worldwide. LangSmith had about 74,000 branded searches, while Weights & Biases had 51,300. LangSmith made up 26.8% of all AI evaluation platform searches we track, and Weights & Biases accounted for 18.6%. When we asked ChatGPT and Google AI Overviews about AI evaluation platforms, LangSmith appeared in three of the five answers and Weights & Biases in two. LangSmith was mentioned before Weights & Biases in every answer that named either.
Who do people search for more?
LangSmith, about 44% more searches than Weights & Biases
Who does AI mention more?
LangSmith, mentioned in 3 of 5 answers, Weights & Biases in 2
Who does AI recommend more?
LangSmith, named ahead of Weights & Biases in 3 of 3 answers
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Top AI evaluation platforms in ChatGPT and Google AI Overviews
In three ChatGPT questions and two Google AI Overviews, LangSmith was mentioned in three out of five: in all three ChatGPT answers, but not in either of the two Google AI Overviews. Weights & Biases was mentioned in two out of five: in two of the three ChatGPT answers, but not in either of the two Google AI Overviews. LangSmith was listed before Weights & Biases in every answer that named either.
Most recommended by AI
Brands get a higher ranking if they are mentioned earlier in the answers.
Braintrust1st- LangSmith2nd
Langfuse3rd
Arize4th
Weights & Biases5th
Promptfoo6th
Patronus AI–
Mentioned by AI
Each dot is one answer, filled in when that answer mentions the brand.
- Arize4 of 5Named in 3 of 3 ChatGPT answersNamed in 1 of 2 Google answers
- Braintrust4 of 5Named in 3 of 3 ChatGPT answersNamed in 1 of 2 Google answers
- Langfuse3 of 5Named in 3 of 3 ChatGPT answersNamed in 0 of 2 Google answers
- LangSmith3 of 5Named in 3 of 3 ChatGPT answersNamed in 0 of 2 Google answers
- Weights & Biases2 of 5Named in 2 of 3 ChatGPT answersNamed in 0 of 2 Google answers
- Promptfoo2 of 5Named in 1 of 3 ChatGPT answersNamed in 1 of 2 Google answers
- Patronus AI0 of 5Named in 0 of 3 ChatGPT answersNamed in 0 of 2 Google answers
See every answer about AI evaluation platforms
5 answers
Asked ChatGPT
“Which AI evaluation platform should I use?”
Asked ChatGPT
“What are the best AI evaluation platforms?”
Asked ChatGPT
“What's the best AI evaluation platform for llm teams?”
Searched Google, AI Overview
“ai evaluation platforms”
Searched Google, AI Overview
“ai model evaluation”
Not named in any answer:
Brands are shown in the order each answer named them. The survey took place in the United States on October 20, 2026.
Is LangSmith or Weights & Biases more popular in search?
This chart shows how often people search Google for LangSmith and Weights & Biases by name. Each line represents a brand's share of searches for all seven AI evaluation platforms we track, month by month, from English-language searches worldwide.
Share of searches by month for LangSmith, Weights & Biases. The figures are in the table below the chart.
View monthly share of searches table
| Month | Langfuse | LangSmith | Weights & Biases | Promptfoo | Arize | Patronus AI | Braintrust |
|---|---|---|---|---|---|---|---|
| Oct 2025 | 29.5% | 29.5% | 31.8% | 4% | 4% | 0.65% | 0.64% |
| Nov 2025 | 29.5% | 29.5% | 31.8% | 4.8% | 3.2% | 0.53% | 0.64% |
| Dec 2025 | 29.6% | 29.6% | 30.5% | 4.8% | 4% | 0.65% | 0.76% |
| Jan 2026 | 33.5% | 27.4% | 28.2% | 5.5% | 3.7% | 0.6% | 1.1% |
| Feb 2026 | 35% | 28.6% | 25.2% | 5.7% | 3.8% | 0.74% | 0.93% |
| Mar 2026 | 29.9% | 24.6% | 21.6% | 20.1% | 2.7% | 0.66% | 0.52% |
| Apr 2026 | 32.8% | 27% | 27.8% | 8.1% | 3% | 0.72% | 0.72% |
| May 2026 | 34.8% | 28.7% | 24.1% | 7% | 3.8% | 0.77% | 0.76% |
| Jun 2026 | 36.2% | 29.8% | 21.4% | 7.3% | 3.3% | 1.2% | 0.79% |
| Jul 2026 | 37.7% | 31% | 18.3% | 7.6% | 3.4% | 1.2% | 0.82% |
| Aug 2026 | 39.5% | 26.6% | 18.3% | 8% | 5.3% | 1.3% | 1% |
| Sep 2026 | 39.8% | 26.8% | 18.6% | 8% | 4.4% | 1.3% | 1.1% |
How has the LangSmith and Weights & Biases comparison changed over the last 12 months?
3 findings
- The lead changed hands 3 times in the 12 months ending September 2026: LangSmith took it in February 2026, Weights & Biases took it in April 2026, LangSmith took it in May 2026.
- Across the 12 months ending September 2026, LangSmith’s share of searches among AI evaluation platforms worldwide moved from 29.5% to 26.8%, and its estimated monthly branded searches held steady at 74K.
- Across the 12 months ending September 2026, Weights & Biases’ share of searches among AI evaluation platforms worldwide moved from 31.8% to 18.6%, and its estimated monthly branded searches moved from 79.6K to 51.3K.
How did search popularity change for AI evaluation platforms worldwide in September 2026?
1 change
Estimated monthly branded searches for Weights & Biases worldwide fell 35.6% over 12 measured months, from 79.6K to 51.3K in September 2026.
How are branded searches counted?
4 search terms
Brandwave collects information about searches that people make online using LangSmith’s and Weights & Biases’ names. When viewed over time, estimated search volumes for these branded terms can be used to understand whether interest in the brands is growing, holding steady, or fading.
LangSmith
1 branded search term
- langsmith
Weights & Biases
3 branded search terms
- wandb
- weights and biases
- weights biases
Other head-to-heads among AI evaluation platforms
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