Quick verdict: The developer security landscape splits sharply between open-source tools (Trivy, Semgrep, OWASP ZAP, Nuclei, Gitleaks, Checkov) that are truly unlimited when self-hosted, and hosted platforms (Snyk, SonarCloud, GitGuardian, StackHawk) with generous free tiers that cap scans, repos, or contributors. For most teams, a stack of OSS tools covers 90% of security needs at zero cost — but hosted platforms add CI/CD integration, dashboards, and triage workflows that save engineering time.
The open-source advantage: Security is the strongest category for OSS tools. Trivy (vulnerability scanning), Semgrep (SAST), OWASP ZAP (DAST), Gitleaks (secrets), and Checkov (IaC) together provide comprehensive coverage with no scan limits, no contributor caps, and no vendor lock-in. The trade-off is self-hosting, configuration, and building your own reporting — which is why hosted platforms like Snyk and GitGuardian thrive despite strong OSS alternatives.
Static Application Security Testing tools analyze source code for vulnerabilities without executing it. The best SAST tools catch SQL injection, XSS, path traversal, and other OWASP Top 10 issues before code reaches production.
Open-source SAST engine with a managed platform. The OSS CLI is unlimited with 2,000+ community rules. The hosted platform (Semgrep Cloud) adds a free tier: 10 contributors, 50 private repos, unlimited public repos. Cross-file analysis, custom rules in YAML, and 30+ languages. The strongest combination of power and accessibility for teams that want managed SAST without paying.
SonarCloud / SonarQube — best for code quality + security
SonarCloud is free and unlimited for open-source projects — code quality, security analysis, and CI/CD integration across 15+ languages. For private repos, self-host SonarQube Community Edition (free, open source). SonarQube covers fewer security rules than dedicated SAST tools but excels at combining quality and security analysis in one workflow.
CodeQL — best for public repos on GitHub Unsourced
GitHub’s semantic code analysis engine. Free for all public repositories with no scan limits. Supports JS/TS, Python, Java, C#, C/C++, Go, Ruby, Swift, Kotlin. The semantic analysis approach catches vulnerabilities that pattern-matching tools miss (taint tracking, data flow analysis). Free for public repos; GitHub Advanced Security license required for private repos (enterprise only).
Snyk Code — real-time SAST with IDE integration
Snyk’s SAST offering provides 100 tests/month on the free tier. Strong IDE integrations (VS Code, IntelliJ) catch issues during development. The 100-test limit is per organization, not per repo — shared across all Snyk products. Best for teams already using Snyk for SCA who want unified vulnerability management.
SCA & Dependency Scanning
Software Composition Analysis tools scan your dependencies for known CVEs and license issues. Critical for supply chain security — most modern applications are 80%+ open-source code by volume.
Snyk Open Source — most comprehensive hosted SCA
200 SCA tests/month on the free tier with unlimited contributing developers. Covers npm, pip, Maven, Gradle, Go modules, NuGet, and more. Automated fix PRs, license compliance, and prioritized vulnerability scoring. The 200-test limit resets monthly — each snyk test or snyk monitor invocation counts as one test per project.
Dependabot — best zero-config SCA for GitHub Unsourced
Free for all GitHub repositories (public and private). Automatically generates pull requests for dependency updates and vulnerability fixes across 30+ ecosystems. Zero configuration needed — GitHub enables vulnerability alerts by default. The simplest SCA onboarding: create a dependabot.yml file and it runs. No scan limits, no contributor caps.
Renovate — best self-hosted dependency bot Unsourced
Open source (AGPL-3.0) with 90+ package manager support — more than any other dependency bot. Available as a self-hosted CLI or free hosted service on GitHub/GitLab via Mend. Supports monorepos, grouped updates, automerge with configurable rules, and advanced scheduling. The free hosted version has no limits.
Goes beyond CVE scanning to detect supply chain attacks: typosquatting, install scripts, obfuscated code, author anomalies. Free for all open-source repos plus your first private repo. The unique “package health score” approach catches threats that traditional SCA tools miss entirely (zero-day supply chain attacks have no CVE to match against).
5 projects, 10 developers, 1 release group on the free tier. Strongest at license compliance — tracks SBOM generation, license obligations, and export control. For teams that need both vulnerability scanning and legal compliance reporting, FOSSA provides both in one tool. The free tier is tight but functional for small projects.
DAST (Dynamic Testing)
Dynamic Application Security Testing tools probe running applications for vulnerabilities by sending crafted requests and analyzing responses. Essential for catching runtime issues that static analysis misses — misconfigurations, authentication bypasses, and server-side injection.
The gold standard of open-source DAST. Apache 2.0 licensed with passive scanning, active scanning, AJAX spider, fuzzing, manual interception proxy, and full CI/CD integration. No scan limits, no application limits, no time restrictions. Community-maintained with continuous updates. The only DAST tool that truly matches commercial offerings (StackHawk, Invicti) on core scanning capability — at zero cost.
Open-source (MIT) scanner with a YAML template system. 9,000+ community-contributed templates covering web apps, APIs, networks, DNS, SSL, and cloud misconfigurations. Extremely fast — can scan thousands of targets in minutes. Best for broad reconnaissance and known-vulnerability detection. Complements ZAP (which excels at deep application testing) with breadth across infrastructure.
Free tier: none. Our own pricing change record, on 2026-04-12, says: Free Developer plan removed, enterprise sales model now We hold no source for this record, so it does not set StackHawk's rating.Read what we recorded →
Free plan with 5 scan hours/month, up to 3 users, and full API access. No credit card required. Covers OWASP Top 10, API-specific vulnerabilities, and provides remediation guidance. The 5-hour limit means approximately 1–2 full scans per month for a typical web application — sufficient for periodic security assessments but not continuous scanning.
Secrets Detection
Secrets detection tools scan your code, commits, and CI/CD pipelines for leaked credentials, API keys, and tokens. A single exposed secret can compromise your entire infrastructure — these tools are non-negotiable for any production codebase.
GitGuardian — most comprehensive hosted secrets scanner Source ↗
Free for up to 25 developers with 420+ secret types detected, unlimited real-time scanning, and 500 historical scan detections. The CLI (ggshield) integrates as a pre-commit hook and CI scanner. The 25-developer limit is generous for startups. Historical scanning (scanning existing commit history) is capped at 500 detections — enough for an initial audit but may not cover large repositories.
Gitleaks — best fully free secrets scanner Unsourced
Open-source (MIT) CLI tool with no limits on repos, scans, or secret types. The GitHub Action is free for all repositories. Configurable via TOML with custom patterns. Faster than TruffleHog for simple git history scanning. The go-to choice for teams that want secrets detection without any vendor dependency or scan caps.
Open-source (Apache 2.0) with a unique advantage: scans not just git repos but also Docker images, S3 buckets, Slack, and 20+ other sources. Detects 800+ credential types with active verification (tests if detected secrets are still valid). The multi-source scanning makes TruffleHog ideal for comprehensive secrets audits across your entire infrastructure.
Container & IaC Security
Container security tools scan images for CVEs and misconfigurations. Infrastructure-as-Code (IaC) scanners check Terraform, CloudFormation, Kubernetes manifests, and Dockerfiles for security issues before deployment.
Open-source (Apache 2.0) multi-target scanner: container images, filesystems, git repos, IaC (Terraform, CloudFormation, Helm, Dockerfile), Kubernetes clusters, SBOMs, and cloud accounts (AWS, GCP, Azure). Covers 20+ language ecosystems with daily-updated CVE databases. The single binary that replaces 3–4 separate tools. CNCF project with strong community support.
Grype — fast container vulnerability scanning Unsourced
Open-source (Apache 2.0) from Anchore. Focused on vulnerability scanning for container images and filesystems. Pairs with Syft (SBOM generator). Supports 20+ ecosystems with daily CVE database updates. Lighter weight than Trivy — does one thing well. Best for teams that want a dedicated, fast container scanner without the broader scope of Trivy.
Open-source (Apache 2.0) by Prisma Cloud (Palo Alto). Scans Terraform, CloudFormation, Kubernetes, Helm, Dockerfile, and 10+ frameworks. 1,000+ built-in policies. Custom policies in Python or YAML. The deepest IaC coverage of any free tool. The CI/CD integration is straightforward — runs as a single CLI command in your pipeline.
CNCF Graduated project (Apache 2.0). Runtime security monitoring for containers, hosts, and Kubernetes. Monitors Linux syscalls and Kubernetes audit events to detect threats in real-time: shell spawning in containers, unexpected network connections, sensitive file access. Unlike scanning tools that check before deployment, Falco watches what actually happens at runtime.
SSL/TLS, Network & Zero Trust
SSL/TLS tools ensure your certificates are valid and properly configured. Zero trust networking replaces traditional VPNs with identity-based access control — increasingly critical as teams go remote and infrastructure moves to the cloud.
Let’s Encrypt — free SSL certificates
Free, automated SSL/TLS certificates trusted by all major browsers. ACME protocol for automated renewal. No limit on certificates. The default choice for any web service that needs HTTPS. Integration via certbot, Caddy, Traefik, nginx, and most cloud providers. There is no reason to pay for basic SSL certificates in 2026.
3 users, 100 devices free with WireGuard-based mesh networking. MagicDNS, exit nodes, subnet routers, ACLs, and split tunneling included. Zero-config networking between devices — no port forwarding, no firewall rules. The free tier is generous for personal use and small teams. Requires personal email domain (no business/custom domain on free).
Starter plan free forever: 5 users, 10 remote networks. Replace traditional VPNs with identity-based access. Each user gets secure access to specific resources rather than the entire network. More enterprise-oriented than Tailscale — better for accessing internal services (databases, admin panels) without exposing them to the internet.
The DevSecOps Cost Trap
Security tools have the widest price gap of any developer tool category. The same capabilities that cost $0 via open-source tools can cost $50,000+/year through hosted platforms. Understanding where to use OSS vs. hosted is the single biggest cost decision in DevSecOps.
Capability
OSS Stack (Self-Hosted)
Hosted Free Tier
Hosted Paid (10-dev team)
SAST
$0 (Semgrep OSS)
$0 (Semgrep Cloud, 10 devs)
$4,000–10,000/yr
SCA
$0 (Trivy + Renovate)
$0 (Snyk, 200 tests/mo)
$5,000–15,000/yr
DAST
$0 (OWASP ZAP)
$0 (StackHawk, 1 app)
$3,000–12,000/yr
Secrets
$0 (Gitleaks)
$0 (GitGuardian, 25 devs)
$3,000–8,000/yr
Container
$0 (Trivy)
$0 (Snyk, 100 tests/mo)
$5,000–20,000/yr
IaC
$0 (Checkov)
$0 (Snyk, 300 IaC tests/mo)
$3,000–8,000/yr
Total
$0
$0 (with limits)
$23,000–73,000/yr
The open-source vs hosted trade-off: Open-source security tools are genuinely enterprise-grade — Trivy, Semgrep, ZAP, and Gitleaks are used by Fortune 500 companies. The cost of self-hosting is engineering time: setting up CI/CD integrations, managing vulnerability databases, building dashboards, and triaging alerts. For a team of 5, the setup cost is 2–3 days. For hosted platforms, it’s 30 minutes. The $23K–$73K/yr price difference buys convenience, not capability.
The scan budget math: Snyk’s free tier gives 200 SCA tests/month. Each snyk test on a project counts as one test. If you have 10 repos and run CI on every PR (5 PRs/day × 20 days = 100 PRs/month × 10 repos = 1,000 tests), you’ll burn through the free tier in 4 days. Teams with active CI/CD pipelines outgrow hosted free tiers fast — which is exactly the business model.
Free for OSS, expensive for private repos: SonarCloud, CodeQL, and SOOS are unlimited for public repositories but require paid plans for private code. This is the most common pricing model in security tooling. If your code is open-source, you get enterprise-grade security for free. If it’s private, the same tools cost thousands per year. Plan accordingly: use OSS-unlimited tools (Semgrep, Trivy, Gitleaks) for private repos, and take advantage of full platform features on your open-source projects.
Best for Each Use Case
Recommendations by use case
Best free SAST → Semgrep
The OSS CLI is unlimited with 2,000+ rules. The hosted platform adds dashboard, triage, and CI/CD automation for up to 10 contributors. Cross-file analysis catches data flow vulnerabilities that simpler pattern matchers miss. The custom rule system (YAML-based) is the most accessible of any SAST tool.
Best free SCA → Dependabot + Renovate
For GitHub repos, Dependabot is zero-config and unlimited. For multi-platform teams or advanced needs (monorepos, grouped updates, automerge), Renovate is the most capable dependency bot with 90+ package managers. Together they cover all SCA needs without scan limits.
Best free DAST → OWASP ZAP
No scan limits, no app limits, full CI/CD integration. The gold standard that commercial DAST tools benchmark against. For teams wanting a simpler managed experience, StackHawk’s free tier (1 app, unlimited scans) provides a modern UI on top of ZAP’s engine.
Best free secrets scanner → Gitleaks
MIT-licensed, fast, configurable, and integrates as a pre-commit hook or GitHub Action. For broader scanning (Docker images, S3, Slack), TruffleHog covers more sources. For a hosted dashboard with team management, GitGuardian’s free tier (25 devs) is the best option.
Best free container scanner → Trivy
One binary that scans containers, filesystems, IaC, Kubernetes, and cloud accounts. Daily CVE database updates, 20+ language ecosystems. The breadth of targets makes Trivy the default choice — it replaces multiple specialized tools with a single scanner.
Best all-in-one platform → Snyk (free tier)
If you want a single platform covering SCA, SAST, containers, and IaC with a unified dashboard, Snyk’s free tier is the most complete. The scan limits (200+100+100+300/month) constrain active CI/CD but are sufficient for periodic scanning and individual developer use.
Best zero-budget full stack → Semgrep + Trivy + Gitleaks + ZAP
This OSS combination covers SAST, SCA, container security, IaC scanning, secrets detection, and DAST — with no scan limits, no contributor caps, and no vendor lock-in. Total cost: $0. Total setup time: 2–3 hours to integrate into CI/CD.
Hidden Costs and Gotchas
Snyk’s test budget burns fast in active CI/CD
Snyk’s 200 SCA tests/month sounds generous, but each CI pipeline run that calls snyk test consumes a test per project. A monorepo with 5 packages running CI on 10 PRs/week burns 200 tests in a single week. The 100 SAST, 100 container, and 300 IaC tests share the same dynamic. Teams with active CI should either reserve Snyk for scheduled scans (not per-PR) or use unlimited OSS alternatives in CI.
CodeQL and SonarCloud are public-only on free tiers
Both tools offer unlimited free scanning — but only for public/open-source repositories. For private codebases, CodeQL requires GitHub Advanced Security ($49/committer/month) and SonarCloud requires a paid plan. If you have a mix of public and private repos, use these tools on public repos and supplement with Semgrep OSS (unlimited for private repos) on private code.
GitGuardian’s historical scan cap
GitGuardian’s free tier includes unlimited real-time scanning (new commits) but caps historical scanning at 500 detections. For a repository with years of commit history, the initial audit may hit this limit before scanning all historical commits. Workaround: use Gitleaks or TruffleHog for the initial historical audit, then enable GitGuardian for ongoing real-time monitoring.
StackHawk’s 1-app limit constrains microservices
StackHawk’s free Developer plan covers 1 application with unlimited scans. For teams with multiple services (API, frontend, admin panel), each additional app requires the Pro plan at $35/app/month. A microservices architecture with 5 services would cost $140/month. Alternative: use OWASP ZAP (unlimited apps) with StackHawk-style CI integration via the ZAP GitHub Action.
Tailscale requires personal email domain
Tailscale’s free tier requires a personal email domain (Gmail, Outlook, GitHub) — custom/business domains require a paid plan. This limits team use: you can’t onboard employees with company email addresses on the free tier. For small teams using personal accounts, the 3-user limit is the real constraint. Headscale (open-source, self-hosted Tailscale-compatible coordination server) removes both limitations.
Pricing Change Timeline
Recent security tool pricing changes tracked in our index.
Date
Provider
Change
Impact
discovered Sep 7, 2026 · effective date unknown
Twingate
The free tier now includes up to 50 resources, not 10. Source ↗
LOW
discovered Sep 7, 2026 · effective date unknown
Socket.dev
The free tier now has 3 members instead of 5, and 500 API quota per hour instead of unlimited. It also includes Socket Basics - SAST, Secrets, and Container scans. Source ↗
MEDIUM
discovered Sep 2, 2026 · effective date unknown
Fingerprint
The free tier now includes a 14-day free trial of the Pro Plus plan and offers 500k Android API calls/mo. Source ↗
LOW
discovered Aug 28, 2026 · effective date unknown
Semgrep
The free tier now includes 60 AI credits and scans up to 10 repositories with a maximum of 10 contributors. Previously 50 private repos (unlimited public). Source ↗
MEDIUM
discovered Aug 28, 2026 · effective date unknown
Virgil Security
The free tier is still offered, but the pricing beyond the free tier is $0.02/month per user beyond 250 users. Source ↗
MEDIUM
discovered Aug 28, 2026 · effective date unknown
Ketch
The free tier now offers full-feature consent management at $0/month with no credit card required, and no limits on jurisdictions or customization. Source ↗
HIGH
discovered Aug 28, 2026 · effective date unknown
Pareto Security
A free 'Starter' plan is available for up to 5 devices. It's presented as a general free offering rather than a specific startup program. Source ↗
MEDIUM
discovered Aug 28, 2026 · effective date unknown
Pullflow
The free tier now has limits: unlimited public repos, unlimited public users, and 5 private repo users. Source ↗
MEDIUM
effective Apr 13, 2026
CodeRabbit
Free tier removed, now 14-day Pro trial only We hold no source for this record, so it does not set CodeRabbit's rating.
LOW
effective Apr 12, 2026
Socket.dev
Private repo free tier expanded from 1 repo to unlimited repos with 1,000 scans/month and up to 5 members Source ↗
LOW
effective Apr 12, 2026
Protectumus
Domain redirects to unrelated 2FA product (Protectimus) We hold no source for this record, so it does not set Protectumus's rating.
LOW
effective Apr 12, 2026
HostedScan
No free tier — plans start at $49/mo We hold no source for this record, so it does not set HostedScan's rating.
LOW
Data Source
How we track this data: the tables on this page were compiled by hand from vendor pricing pages. They do not come from the catalogue behind our search and MCP tools. Prices and limits are for free tiers only — paid tier comparisons use publicly available list prices. Compiled 2026-04-01, not re-checked since. Check data freshness.
A source check reads each cited page for that service's name and a price; the figures in the tables above are from our own records.
FOSSA — We read that on 2026-09-09 from fossa.com/pricing, and our check recorded: the page names FOSSA as "fossa" and states "$ 2"
GitGuardian — We read that on 2026-09-07 from gitguardian.com/pricing, and our check recorded: the page names GitGuardian as "gitguardian" and states "$0"
Gitleaks — the page we cite for this offer states no amount, tier or rate we can read
Grype — the page we cite for this offer states no amount, tier or rate we can read
Socket.dev — We read that on 2026-09-07 from socket.dev/pricing, and our check recorded: the page names Socket.dev as "socket" and states "$0"
SOOS — we could not read the page we cite for this offer
StackHawk — no catalogue record
Tailscale — We read that on 2026-09-05 from tailscale.com/pricing, and our check recorded: the page names Tailscale as "tailscale" and states "$0"
Trivy — the page we cite for this offer states no amount, tier or rate we can read
TruffleHog — the page we cite for this offer states no amount, tier or rate we can read
Twingate — We read that on 2026-09-07 from twingate.com/pricing, and our check recorded: the page names Twingate as "twingate" and states "$15"
Frequently Asked Questions
What is the best free security service in 2026?
We publish no ranking of these. Nothing we record measures popularity or generosity, so naming a best or a top few would be our preference rather than our data. We hold 53 Security services in our catalogue, each with the free tier terms and the date we last verified them. This page compares them on free tier limits, what each charges past them, and lock-in risk; the table above carries the figures side by side. Our ranking rule is published at /criteria.
Which security free tier is most generous?
Free tier generosity varies by use case. Some providers offer more storage, others more compute or API calls. Our comparison table above shows exact limits side-by-side so you can evaluate based on what matters most for your workload.
How do security free tiers compare on limits?
Each provider structures free tier limits differently — some cap storage, others cap requests or compute hours. Our comparison table provides exact numbers for each provider. Check the growth cost analysis section to understand what you'll pay when you exceed free tier limits.