Prolific records 18,697,671 monthly visits with -1.8% month-over-month growth and Paid pricing. TestFit records 56,871 monthly visits with -14.9% growth and Paid, Contact for Pricing pricing.
High-quality human data for AI training, evaluation, and research
Automate site plans and test development deals in hours, not weeks
| Dimension / Metric | | |
|---|---|---|
| Official Domain | prolific.com | testfit.io |
| Pricing Model | Paid | Paid, Contact for Pricing |
| Monthly Visits | 18.7M (18,697,671) | 56.87K (56,871) |
| MoM Traffic Delta | -352.04K (-1.8%) | -9.93K (-14.9%) |
| Primary Market & Share | 🇺🇸 United States (48.8%) | 🇺🇸 United States (47%) |
| Direct Visits / mo | 12.98M | 30.29K |
| User Rating | 4.6 | 4.4 |
| Supported Platforms | Website | Website |
High-quality human data for AI training, evaluation, and research
Filter participants by detailed demographic, professional, and behavioural criteria and reach narrow or representative samples rather than a generic crowd.
Collect human preference data for model fine-tuning, run safety evaluations and red-teaming, and use a feedback API to plug humans into automated pipelines.
Attention checks, honesty screening, and approval workflows help filter out careless or fraudulent responses before you analyse results.
Publish a study and begin collecting responses quickly, with tooling that supports screening, quotas, and longitudinal designs.
Automate site plans and test development deals in hours, not weeks
Map any parcel or draw custom boundaries, then generate a buildable plan with road layout, turning radii and topography handled so you avoid redesign later.
Produce optimal surface and structured parking layouts, set custom stalls and drive aisles, and validate parking ratios without manual drafting.
Overlay parcel, environmental and zoning data, model 3D terrain with cut-and-fill analysis, and check power and utilities infrastructure before design assumptions harden.
Connect financial models directly to your design, with live pro forma figures and import of your own Excel templates, to see whether a deal pencils.
Large consumer panel for market research surveys, but lacks Prolific's specialized focus on academic studies and AI tuning.
Large consumer panel for market research surveys, but lacks Prolific's specialized focus on academic studies and AI tuning.
SpecialistThe environments frontier AI trains on, and the agents that do the recurring work
SpecialistThe environments frontier AI trains on, and the agents that do the recurring work
Enterprise-grade data annotation and AI alignment workforce, but less self-serve for academic study recruitment and casual surveys.
Free / Open-sourceAI property data, skip tracing and direct mail for real estate investors
Free / Open-sourceAI property data, skip tracing and direct mail for real estate investors
SpecialistAI data infrastructure for building production-grade models
SpecialistAI data infrastructure for building production-grade models
SpecialistSpecializes in video-based consumer interviews and AI qualitative analysis, but less focused on quantitative academic survey panels.
SpecialistSpecializes in video-based consumer interviews and AI qualitative analysis, but less focused on quantitative academic survey panels.
Free / Open-sourceAI interior design, floor plans and 3D models for every home project
Free / Open-sourceAI interior design, floor plans and 3D models for every home project
SpecialistSources verified B2B professionals and healthcare experts for specialized research, but lacks broad general-population academic panels.
SpecialistSources verified B2B professionals and healthcare experts for specialized research, but lacks broad general-population academic panels.
Free / Open-sourceRedesign any room from a photo with AI, then shop the exact furniture
Free / Open-sourceRedesign any room from a photo with AI, then shop the exact furniture
Free / Open-sourceOpen-source data labeling and evaluation platform for AI workflows, but requires bringing your own annotation workforce.
Free / Open-sourceOpen-source data labeling and evaluation platform for AI workflows, but requires bringing your own annotation workforce.
Free / Open-sourceAI plan review and permitting software for cities and design teams
Free / Open-sourceAI plan review and permitting software for cities and design teams
Free / Open-sourceInstant AI floor plans, room redesigns and flooring visuals
Free / Open-sourceInstant AI floor plans, room redesigns and flooring visuals
