Free Security Scanner Ranking 2026: Honest Comparison

The best free security scanner in 2026 depends on one question: what does your app actually look like? A Next.js SaaS has a different threat surface than a Python CLI tool or a containerized microservice. The right free scanner for each is different.

We tested seven free security scanning options against the same set of repositories — a mix of Next.js, Django, and Go projects. Here's the honest ranking, with what each tool actually catches and where it falls short.

Pricing verified February 2026.

The Ranking Criteria

To make this comparison fair, we evaluated each tool on:

• Coverage breadth — how many vulnerability types does it catch?
• Setup friction — how long until you see results?
• Free tier limits — what do you actually get before hitting a paywall?
• Finding quality — are findings actionable? Or just CVE numbers?
• False positive rate — does it bury you in noise?

Let's go through the list.

Quick Comparison Table

#1 Data Hogo — Best Coverage Breadth for Free

Data Hogo's free plan covers more vulnerability types in a single scan than any other option on this list. Connect your GitHub repo, hit scan, and within minutes you get findings across six categories:

• Secrets and credentials committed to the repo
• Vulnerable dependencies (npm, pip, Go modules)
• Code pattern vulnerabilities — 250+ rules covering injection, broken auth, SSRF, and more
• Configuration issues and insecure defaults
• Security headers on your deployed URL
• Supabase RLS policies and Firebase security rules

The setup is fast. No CI configuration, no Docker container to run, no YAML to write. That matters for a developer who wants to check a repo and get back to shipping.

What the free tier includes:

• 3 scans per month
• 1 public repository
• Full detail on low, medium, and informational findings
• Critical and high findings visible as a count (not detailed until you upgrade)

That last point is intentional — you'll know you have 3 critical findings, but you won't see exactly what they are or where they live without a paid plan. It's not generous, but it's honest: you get real signal for free, and you know whether it's worth paying for the details.

What it misses: Cloud infrastructure (AWS IAM, S3, GCP). No container scanning. For repos and web apps — which is the full surface for most projects — coverage is complete.

Check your repo with the free plan →

#2 GitHub Advanced Security — Best Free Option for Public Repos

For open source projects hosted on GitHub, this is the strongest free option. The limits disappear entirely for public repos.

CodeQL is GitHub's static analysis engine. It builds a semantic model of your code — not just pattern matching — and queries it for vulnerability patterns. SQL injection across complex data flow paths, XSS that crosses file boundaries: CodeQL finds things simpler tools miss. It's genuinely impressive technology, and it's free for public repos.

Dependabot sends alerts and opens automated pull requests when your dependencies have known vulnerabilities. Free for all repos, public and private, regardless of GitHub plan.

Secret scanning on public repos catches common credential patterns in commits. Also free.

What it misses:

• Security header scanning
• Database rule analysis (RLS, Firebase)
• A unified security score
• Auto-fix for code vulnerabilities (Dependabot creates PRs for dependency updates, not code fixes)
• Plain-language explanations — findings are technical and assume familiarity with vulnerability classes

For private repos, CodeQL costs $49 per committer per month. That adds up fast for a team of three.

If you maintain open source and want PR-gate security scanning at zero cost, start here. For private projects, the math shifts.

#3 Semgrep — Best for Custom Detection Rules

Semgrep is a static analysis tool (SAST) that's free for teams with 10 or fewer contributors. It has over 1,000 community-maintained rules and lets you write custom YAML rules tailored to your codebase.

If you have a security engineer who wants to write detection logic — say, a rule that flags every time your app handles user-uploaded files without a specific validation wrapper — Semgrep is the right tool. The custom rule system is genuinely powerful.

What it misses:

• Secrets detection (you'd need Gitleaks or similar alongside it)
• Dependency scanning (SCA) — Semgrep doesn't look at your package.json CVEs
• Security header scanning
• Database rule analysis
• Plain-language explanations for developers without a security background

It requires CLI or CI setup. No SaaS dashboard on the free tier. For a developer who wants to know "is my repo safe," the setup-to-answer ratio is high.

Paid tier: $40/contributor/month. Strong tool, different use case.

#4 Gitleaks — Best Free Secret Scanner

If you specifically need to detect committed secrets — API keys, tokens, credentials — Gitleaks is the gold standard free option. It's open source, runs as a CLI or GitHub Action, and is fast.

# Run against current repo
gitleaks detect --source .
 
# Scan git history for secrets in past commits
gitleaks detect --source . --log-opts=--all

Gitleaks is what Data Hogo uses under the hood for its secrets detection engine. The pattern library covers 40+ secret types including AWS keys, Stripe tokens, GitHub PATs, and database connection strings.

What it misses: Everything except secrets. No code analysis, no dependency scanning, no headers. It's a single-purpose tool — excellent at that purpose.

#5 OWASP Dependency-Check — Best Free SCA for Java

OWASP Dependency-Check is a Software Composition Analysis (SCA) tool that checks your dependencies against the NVD database and other vulnerability sources. It's mature, maintained, and free.

Particularly strong for Java/Maven/Gradle ecosystems. JavaScript support exists but is less comprehensive than npm audit.

The catch: It's CLI-only and self-hosted. The HTML reports are detailed but verbose — you'll get CVE numbers and CVSS scores without plain-English explanations of what they mean. If you're a developer without a security background, parsing a Dependency-Check report takes work.

# Scan a Node.js project
dependency-check --project "myapp" --scan ./package.json --out ./reports

What it misses: SAST, secrets, configuration analysis, headers. Single-concern tool.

#6 Trivy — Best Free Container Scanner

Trivy from Aqua Security is the standard tool for scanning Docker images, Kubernetes manifests, and IaC (Terraform, Helm) for vulnerabilities. If you have containers in your workflow, Trivy is probably already in your CI pipeline.

# Scan a Docker image
trivy image node:18-alpine
 
# Scan a repo for secrets and dependencies
trivy fs .

Trivy also does basic repository scanning (dependencies and secrets), but its primary value is in container contexts. For a typical web app without a containerized deployment, the value proposition is limited.

What it misses: SAST code pattern analysis, security headers, database rules, unified security score.

#7 SonarCloud — Best for Code Quality Plus Basic Security

SonarCloud's primary value is code quality — maintainability, test coverage, technical debt. Security scanning is part of the offering but secondary to quality metrics.

Free for public open source repos. Private repos cost roughly €30+/month based on lines of code.

What it misses: Secrets detection, dependency scanning, security headers, database rules. If your main concern is "did I commit a key" or "is my RLS policy broken," SonarCloud won't catch it.

Strong tool for open source maintainers who care about code quality. Not the right fit if security is the primary concern.

How to Choose

You want full-surface coverage with minimal setup: Data Hogo. Three scans per month, no configuration. Start there, see what comes back.

You maintain open source on GitHub: GitHub Advanced Security. Free, no limits, CodeQL is genuinely excellent for public repos.

You want to write custom detection rules: Semgrep. The custom rule system is the most powerful on this list.

You specifically need secret scanning in CI: Gitleaks as a GitHub Action. Fast, accurate, free, runs on every push.

You work with Docker/Kubernetes: Trivy. The standard in that ecosystem.

You care about code quality as much as security: SonarCloud. Especially for open source projects.

Most developers building a real web app — a Next.js SaaS, a Django API, a Rails app — want the first option. The security risks in AI-generated code are real and consistent, and the fastest path to knowing if your repo is safe is a full-surface scan with no configuration overhead.

Scan your repo free →

Frequently Asked Questions

What is the best free security scanner in 2026?

For full-coverage scanning (secrets, dependencies, code patterns, headers, DB rules) with no setup required, Data Hogo's free plan is the strongest option for individual developers. For open source projects on GitHub, GitHub Advanced Security (CodeQL + Dependabot) is free with no limits. For teams who want custom detection rules, Semgrep is free for up to 10 contributors.

Is there a free security scanner that covers both code and dependencies?

Yes. Data Hogo's free plan covers code patterns (250+ Semgrep rules), dependency scanning, secrets detection, configuration review, security headers, and database rules — all in one scan. GitHub Advanced Security covers CodeQL (code) and Dependabot (dependencies) for free on public repos.

Can I scan a private GitHub repository for free?

Dependabot vulnerability alerts are free on all private GitHub repos. CodeQL (SAST scanning) on private repos requires GitHub Advanced Security at $49/committer/month. Data Hogo's free plan covers 1 public repo — private repo scanning starts at $12/month on the Basic plan.

What does a free security scanner miss compared to a paid one?

Free tiers typically limit scan counts, hide critical/high findings, or restrict coverage to one vulnerability type. Most free scanners don't include auto-fix PR generation. Data Hogo's free tier shows all low, medium, and informational findings in full — critical and high findings are visible as a count but not detailed until you upgrade.

How often should I scan my repository?

Before every major release and after merging significant AI-generated code. Weekly scans are reasonable for active projects. Most developers run a scan when setting up a new project and then whenever they add a new integration, dependency, or AI-generated feature.