BasilStack – AI Model Evaluation for Real-World Scenarios

Don't guess your AI stack

Know how it behaves before you ship.

Test models, prompts, and parameters on real scenarios — and catch risky responses before users do.

Set up evaluations in minutesUse your own data and real inputsExport and share results

Works with your use case

Compatible with leading LLM providers

💬Customer Support💻Code Generation⚖️Legal Documents🛡️Content Moderation📄Invoice Processing📝Product Descriptions✉️Email Writing📊Data Analysis🌐Translation📋Summarization🔍Research

GPT-5 ProClaude Sonnet 4.5Gemini 2.5 ProGPT-4.1Claude Opus 4.1Gemini 2.5 FlashGPT-4oClaude Haiku 4.5Gemini 2.5 Flash-LiteGPT-5GPT-4.1 MiniGPT-4o MiniGPT-5 MiniGPT-4.1 NanoGPT-3.5 TurboGPT-5 Nano

Results reflect user-configured prompts and constraints. Not benchmarks.

Real evaluation example

See how a single scenario behaves across models

Run the same scenario across multiple models

Compare outputs, latency, and cost under identical conditions

Export results for review or sharing

Powerful features

Evaluate models the way your product actually uses them

Compare responses, cost, and latency across models using your real scenarios — before you ship.

Compare models side-by-side

Test 15+ models in parallel

Supports OpenAI, Anthropic, and Google

Same prompt, same context, same constraints

Test with your real data

Upload PDFs, Word docs, and text files

Add URLs for website context

See how retrieval and context actually affect responses

Understand tradeoffs clearly

Response latency and variability

Cost per run and per scenario

Qualitative differences in tone, confidence, and claims

Take results with you

Export responses and metrics

Save and label scenarios

Re-run evaluations as configs change

Start testing in minutes

No complex setup. No coding required.

Write prompt

Enter your test prompt in seconds

Step 1 of 3

~30 seconds

Write prompt

Enter your test prompt in seconds

Run test

Test across multiple AI models instantly

Get results

View side-by-side comparison instantly

~30 seconds

Advanced testing

Go beyond side-by-side comparisons

Stress-test model behavior before it reaches production.

See how configuration changes behavior

•Compare temperature, max tokens, and system settings

•Observe effects on verbosity, confidence, and hallucinations

•Identify safe defaults for production

Test prompts like you test code

•A/B test different prompt structures

•Compare tone, clarity, and failure modes

•Catch risky wording before users do

Track behavior over time

•Re-run scenarios as models or prompts change

•Compare results across versions

•See regressions before they hit production

Start free. Upgrade when you're ready.

7-day free trial · No credit card required · Includes up to 20 evaluations

MonthlyYearly (Save 17%)

7-Day Trial

Solo

For individual developers and early projects

$29.99 / month

after free trial

✓100 evaluations/month
✓All supported AI models
✓RAG files: 5
✓RAG pages (web): 10
✓Export results (JSON, XLS)
✗Priority support

7-Day Trial

Professional

For teams evaluating models before production

$49.99 / month

after free trial

✓200 evaluations/month
✓All supported AI models
✓RAG files: 25
✓RAG pages (web): 50
✓Export results (JSON, XLS)
✓Priority support

Prices are exclusive of applicable taxes. Taxes may apply.

Ready to build with confidence?

Test how models behave in your real scenarios — before users do.

7-day trial • No card required