A head-to-head comparison of Foundry and Tenderly — pricing, the features that actually differ, and which one fits which use case.
Blazing-fast Rust-based Solidity testing framework with built-in fuzzing and invariant testing
Smart contract observability platform for simulation, debugging, monitoring, and alerting in production
These are the 10 capabilities where the two tools genuinely diverge — the rest of their feature sets overlap.
| Capability | Foundry | Tenderly |
|---|---|---|
| Local Node | Yes | No |
| Mainnet Forking | Yes | — |
| Language | Solidity (tests) | — |
| Test Framework | forge-std | — |
| Plugin Ecosystem | Growing (smaller than Hardhat) | — |
| Debugging | Yes | — |
| Deployment System | Forge scripts | — |
| Open Source | Yes | No |
| Fuzz Testing | Yes | — |
| Invariant Testing | Yes | — |
| Feature | Foundry | Tenderly |
|---|---|---|
| Local Node | ✓ | ✗ |
| Mainnet Forking | ✓ | — |
| Language | Solidity (tests) | — |
| Test Framework | forge-std | — |
| Plugin Ecosystem | Growing (smaller than Hardhat) | — |
| Debugging | ✓ | — |
| Deployment System | Forge scripts | — |
| Open Source | ✓ | ✗ |
| Fuzz Testing | ✓ | — |
| Invariant Testing | ✓ | — |
| Transaction Debugger | — | ✓ |
| Simulation Api | — | ✓ |
| Production Monitoring | — | ✓ |
| Alert System | — | ✓ |
| Virtual Testnets | — | ✓ |
| Rpc Provider | — | ✓ |
| Multi Chain | — | ✓ |
| Team Collaboration | — | ✓ |
Both tools are free to use — costs come from network or usage fees.
Foundry
Free
Tenderly
$39/mo
$390/yr billed annually
Tenderly
$99/mo
$990/yr billed annually
Tenderly
Custom
Watch out: Smaller plugin ecosystem than Hardhat — some tooling requires custom solutions.
Watch out: Free tier limits simulations to 5/month — quickly exhausted in active development.
Foundry edges ahead on our editorial score (4.8/5), but these tools aren’t straight substitutes. Pick Foundry when 5–20x faster test execution than hardhat — critical for large suites and audit pipelines matters most to your workflow; pick Tenderly when visual transaction debugger is the most accessible evm debugging tool available is the priority. The deciding factor is usually the trade-off you can least afford — Foundry means accepting that smaller plugin ecosystem than hardhat — some tooling requires custom solutions, while Tenderly means free tier limits simulations to 5/month — quickly exhausted in active development.
Foundry carries the higher editorial rating (4.8/5 vs 4.6/5), but they solve different problems. Foundry is the stronger pick when you need 5–20x faster test execution than hardhat — critical for large suites and audit pipelines. Tenderly wins when visual transaction debugger is the most accessible evm debugging tool available.
Both tools are free to use, with costs coming from network or usage fees rather than subscriptions.
Foundry's main limitation is that smaller plugin ecosystem than hardhat — some tooling requires custom solutions. For Tenderly, free tier limits simulations to 5/month — quickly exhausted in active development. Weigh these against how you actually plan to use the tool.
In most cases yes — many teams run both, using each where it's strongest. Since Foundry leads on 5–20x faster test execution than hardhat — critical for large suites and audit pipelines and Tenderly on visual transaction debugger is the most accessible evm debugging tool available, the two are often complementary rather than mutually exclusive.