Smart Contract Security Audit Services
Thorough manual review combined with invariant testing — the most rigorous approach to smart contract security available today.
Why Invariant-Powered Audits Find More Bugs
Traditional audits rely on manual review alone. Our approach pairs experienced security researchers with invariant test suites that systematically explore your contract's state space. This means we catch not just the obvious bugs, but edge cases that only surface under complex multi-transaction sequences — the kind that cause real exploits in production.
Audit Methodology Comparison
Not all audit approaches are equal. Here's how invariant-powered audits stack up against alternatives.
| Approach | State Space Coverage | Multi-Tx Sequences | Ongoing Protection | Cost Efficiency |
|---|---|---|---|---|
| Invariant Testing + Manual Review (Recon) | Exhaustive | Yes — stateful fuzzing | Yes — reusable test suite | High — catches more per dollar |
| Traditional Manual Audit | Limited to reviewer skill | Rarely tested | No — point-in-time | Medium |
| Automated Scanners (Slither, etc.) | Pattern-based only | No | No | Low cost but low coverage |
| Formal Verification | Mathematical proof | Yes — if modeled | Breaks on code changes | Very expensive |
What You Get
Every Recon audit includes a detailed findings report, severity classification, remediation guidance, and a full invariant test suite you keep. The test suite continues protecting your codebase after the audit — run it in CI, extend it as you ship new features, or use Recon Pro to run it in the cloud.
Chains and Languages Supported
Our deepest expertise is in Solidity audit — we audit Solidity smart contracts across all major EVM-compatible chains: Ethereum, Arbitrum, Optimism, Base, Polygon, BSC, Avalanche, and more. Our blockchain security methodology covers everything from token audit and ERC-20 compliance to complex DeFi protocol invariants. EVM tooling supports Foundry, Hardhat, and custom build setups with cloud fuzzing via Recon Pro.
For Rust (Solana, CosmWasm) and Go (Cosmos SDK), we pair manual review with language-native fuzzers — cargo-fuzz, go test -fuzz — and coverage-driven iteration.
We also review C/C++ cryptographic libraries and protocol implementations using libFuzzer and AFL++.
For Move, Cairo, ZK circuits (Circom, Noir), and Soroban, we offer manual security review with property specification.
Frequently Asked Questions
How much does a smart contract audit cost?
Audit pricing depends on codebase size, complexity, and scope. A typical engagement for a focused protocol (1,000-5,000 nSLOC) ranges from $30K-$80K. Contact us for a tailored quote — we'll review your codebase and provide a fixed price within 48 hours.
How long does an audit take?
Most audits take 2-4 weeks depending on codebase complexity. We can accommodate faster timelines for time-sensitive launches. The invariant test suite is delivered alongside the audit report.
What's included in the audit deliverables?
You receive a detailed findings report with severity ratings, detailed descriptions, remediation recommendations, and proof-of-concept exploits for critical and high findings. You also get a full invariant test suite that you keep and can run indefinitely.
Do you audit protocols that are already deployed?
Yes. We regularly audit live protocols before upgrades, new feature deployments, or as part of ongoing security programs. We can fork mainnet state for realistic testing.
Do you need a smart contract audit?
If your contract holds user funds, has admin roles, is upgradeable, or integrates with external protocols, you need an audit. See our full decision checklist to determine the right type of security review for your situation.
What makes Recon different from other audit firms?
We combine top-tier manual review with invariant testing for comprehensive smart contract security. This means you get both expert human judgment and systematic state-space exploration. Our team includes a top Code4rena judge, the creator of EchidnaToFoundry, and engineers who've protected hundreds of millions in TVL.
How do I choose the best smart contract auditor?
Look for firms that deliver executable test suites, not just PDF reports. Ask for case studies with real bugs found and verify they do invariant testing. Check whether they've got experience on your chain and framework. A good auditor should also help you understand whether you need an audit at all and what level of engagement fits your budget.
Ready to Secure Your Protocol?
Get a quote for your smart contract audit in 48 hours.
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Smart Contract Audit
A smart contract audit is a systematic security review of blockchain smart contract code to identify vulnerabilities, logic errors, and potential attack vectors before deployment.
Smart Contract Security
Smart contract security covers the practices, tools, and methodologies used to identify and prevent vulnerabilities in blockchain smart contracts before and after deployment.
AI Auditing
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