ENS Domain Cost Calculator
Calculate Ethereum Name Service (ENS) domain registration costs. Estimate annual fees by name length plus gas costs for .eth domain registration and renewal.
Smart Contract Audit Cost Calculator
Estimate smart contract audit costs based on lines of code, complexity, and auditor rates. Plan your security budget for Solidity and EVM-based contract audits.
$
%
Estimated Audit Cost⧉
$30,000.00
Base: $20,000.00 × 1.5x complexity
Re-audit Estimate⧉
$7,500.00
25% of audit cost
Total Budget⧉
$37,500.00
Sum of all values
Effective $/Line⧉
$15.00
Estimated Timeline⧉
4 weeks
Approximate review period
Planning notes, formulas, and examples
About the Smart Contract Audit Cost Calculator
A smart contract audit is one of the most critical steps before deploying any project that handles real funds. Auditors review your Solidity (or Vyper, Rust, etc.) code line by line, looking for vulnerabilities, logic errors, and gas optimization opportunities. The cost of an audit depends primarily on the size of the codebase, its complexity, and the reputation of the auditing firm.
Audit costs typically range from $5 to $15 per line of code for manual review, with additional fees for complex DeFi protocols, novel cryptographic implementations, or tight timelines. Top-tier firms like Trail of Bits, OpenZeppelin, and Consensys Diligence often charge premium rates but provide the highest confidence level.
This calculator helps you estimate audit costs before writing a single line of Solidity. By understanding the budget required, you can plan your codebase size, choose the right auditor tier, and set aside appropriate funds from your treasury or raise. This calculator is for educational purposes only and does not constitute financial advice.
When This Page Helps
Smart contract exploits have caused billions in losses across DeFi and NFT projects. An audit is essential insurance, but costs vary wildly — from $5,000 for a simple token to $500,000+ for complex DeFi protocols. This calculator helps you budget accurately based on your project's actual complexity, avoiding sticker shock when you request audit quotes.
How to Use the Inputs
- Enter the approximate number of lines of Solidity/Vyper code in your project.
- Select the complexity level: low (simple token/NFT), medium (standard DeFi), or high (novel protocol).
- Enter the per-line rate (typically $5-$15 depending on auditor tier).
- Review additional complexity multipliers applied to the base cost.
- See the estimated total audit cost and compare against your budget.
- Use the result to request quotes from auditors with realistic expectations.
Formula used
Base Cost = Lines of Code × Rate per Line ($/line)
Complexity Multiplier: Low = 1.0, Medium = 1.5, High = 2.5
Estimated Audit Cost = Base Cost × Complexity MultiplierExample Calculation
Result: $30,000
A 2,000-line smart contract at $10/line gives a base cost of $20,000. With medium complexity (1.5x multiplier for standard DeFi logic), the estimated audit cost is $30,000. Top-tier auditors may charge more; smaller firms may charge less.
Tips & Best Practices
- Reduce audit costs by keeping your codebase concise — every unnecessary line costs money to audit.
- Use well-tested libraries like OpenZeppelin contracts to reduce custom code that needs auditing.
- Get multiple audit quotes — prices vary widely between firms and independent auditors.
- Budget for a re-audit of any code changes made after the initial audit findings.
- Consider a preliminary automated audit (Slither, Mythril) to catch obvious issues before paying for manual review.
- Factor in 2-8 weeks lead time — rushing an audit significantly increases cost.
- High-value protocols should budget for multiple independent audits from different firms.
What Auditors Look For
Smart contract auditors examine code for reentrancy attacks, integer overflow/underflow, access control flaws, flash loan vulnerabilities, oracle manipulation, front-running exposure, and gas optimization issues. They also verify that the code's behavior matches the project's specification and documentation.
Complexity Factors That Increase Cost
Several factors push audit costs above the base per-line rate: novel cryptographic implementations, cross-chain bridge logic, complex tokenomics with multiple interacting contracts, upgradeable proxy patterns, and protocols that interact with many external DeFi protocols. Each additional interaction surface increases the attack surface.
Preparing for an Audit
Before submitting code for audit, ensure comprehensive test coverage (aim for >95%), write clear documentation and specifications, use NatSpec comments, run automated analysis tools, and freeze the codebase. Well-prepared codebases cost less to audit because auditors spend less time understanding the intent.
The Economics of Security
Spending $50,000 on an audit may seem expensive, but it's trivial compared to the cost of an exploit. Major DeFi exploits have regularly reached eight-figure losses, so audits, bug bounties, and other controls should be budgeted as part of a broader security program. A common planning range is 5-15% of development cost for security work.
Sources & Methodology
Last updated:
Frequently Asked Questions
Simple token or NFT contracts cost $5,000-$15,000. Standard DeFi protocols cost $20,000-$80,000. Complex novel protocols can cost $100,000-$500,000+. The primary factors are code size, complexity, and auditor reputation.
Most audits take 2-6 weeks for review plus 1-2 weeks for the report. Complex protocols may take 8-12 weeks. Rush audits are possible but cost 50-100% more. Plan your audit well before your planned launch date.
No audit can guarantee 100% safety. Audits significantly reduce risk by catching known vulnerability patterns and logic errors, but novel attack vectors can emerge after deployment. Think of audits as essential risk reduction, not elimination.
For protocols handling significant value (>$10M TVL), multiple independent audits are strongly recommended. Different auditors catch different issues. Many major DeFi protocols undergo 2-3 separate audits before launch.
Automated tools (Slither, Mythril, Echidna) scan for known patterns quickly and cheaply. Manual audits involve human experts who understand business logic, find novel vulnerabilities, and verify the code does what it's supposed to do. Both are recommended.
Top-tier firms include Trail of Bits, OpenZeppelin, Consensys Diligence, Certora, and Spearbit. Mid-tier firms like Hacken, PeckShield, and CertiK offer more affordable options. Independent auditors on platforms like Code4rena offer competitive rates.
Internal review is valuable but should never replace an external audit for production contracts. Developers are prone to blindspots in their own code. At minimum, use automated tools and have a different developer review the code.
The auditor will flag critical, high, medium, and low severity issues in their report. You fix the issues and typically the auditor re-reviews the fixes (sometimes included in the original fee, sometimes extra). Never deploy with unresolved critical findings.
More in this topic
NFT Arweave Storage Cost Calculator
Calculate one-time Arweave permanent storage costs for NFT collections. Estimate total AR tokens needed based on file sizes and current network rates.
NFT IPFS Storage Cost Calculator
Calculate IPFS pinning costs for NFT metadata and media files. Compare Pinata, Infura, and other providers to estimate monthly and annual storage expenses.