Firewall Compliance Checker Calculator

Run a Compliance Check

Enter your control signals, then calculate a weighted compliance score.

Organization / Project (optional)

Used in exports only.

Environment

Compliance Framework

Firewall Type

Rule Count

Large rule sets usually need tighter governance.

Rules Documented (%)

Documentation supports audits and incident response.

Review Frequency

Default Deny Enabled

A baseline deny policy limits implicit exposure.

Traffic Logging

Change Management for Rules

Tracks approvals, owners, and rollback plans.

Segmentation Strength

Separation reduces blast radius for breaches.

Admin MFA Required

Days Since Last Security Update

Shorter intervals typically reduce known exploit risk.

Unused / Stale Rules (%)

High stale percentages inflate complexity and mistakes.

Externally Reachable Ports (count)

Counts services exposed to the internet or untrusted networks.

Example Data Table

Sample environments and scores to illustrate typical outputs.

Environment	Framework	Docs %	Review	Default Deny	Logging	Segmentation	Score	Status
Production	PCI DSS	96	Monthly	Yes	Inbound + Outbound	Strong	92.6	Compliant
DMZ	SOC 2	88	Quarterly	Yes	Inbound only	Partial	78.4	Needs Improvement
Staging	ISO/IEC 27001	72	Semiannual	No	None	Partial	55.7	Non-compliant
Branch Office	CIS Controls	85	Annual	Yes	Outbound only	None	63.2	Non-compliant
Development	NIST SP 800-53	80	Quarterly	Yes	Inbound + Outbound	Partial	74.9	Needs Improvement

Formula Used

The calculator produces a weighted compliance score from 0 to 100:

Compliance Score = Σ (Control Scoreᵢ), where each Control Scoreᵢ ≤ Weightᵢ

Rule documentation: 15 × (Documented% ÷ 100)
Review cadence: Monthly 15, Quarterly 10, Semiannual 6, Annual 3, Never 0
Default deny: Yes 12, No 0
Logging: None 0, Single-direction 6, Both directions 10
Change management: Yes 10, No 0
Segmentation: None 0, Partial 6, Strong 10
Admin MFA: Yes 8, No 0
Patch recency: ≤30d 10, 31–90d 7, 91–180d 4, >180d 1
Rule hygiene: Unused ≤5% 5, 6–15% 3, 16–30% 1, >30% 0
Exposed services: Ports ≤2 5, 3–10 3, 11–25 1, >25 0

Status thresholds: Compliant ≥85, Needs Improvement 70–84.9, Non-compliant <70.

How to Use This Calculator

Choose the environment and framework that best matches your audit scope.
Enter documentation percentage and review cadence from policy or ticket records.
Confirm default-deny, logging coverage, and change management enforcement.
Select segmentation strength and whether administrative access requires MFA.
Provide days since the last security update and estimate stale rule percentage.
Count externally reachable ports from scans or asset exposure inventories.
Click Check Compliance to view score, breakdown, and actions.
Use Download CSV or Download PDF for reports.

Documentation and Evidence Quality

Firewall audits typically start with proof: who approved each rule, why it exists, and when it was last validated. This calculator converts documentation coverage into a weighted score so teams can quantify gaps. Include business justification, data classification, source and destination objects, service definitions, and ticket references. A move from 70% to 90% documented rules often shortens review cycles because owners and expiry dates are already visible, and exceptions can be defended with evidence.

Review Cadence and Drift Control

Rule bases drift as projects end, vendors change, and temporary permits linger. Monthly or quarterly reviews catch stale objects, shadowed rules, duplicated entries, and outdated NAT translations before they become exposure. The scoring model rewards shorter review cycles because they correlate with faster remediation and clearer accountability between security, network operations, and application teams. Track outcomes such as rules removed, tightened, or time-limited, and log the reviewer and decision date.

Default-Deny and Logging Coverage

Default-deny is a baseline control that forces explicit allowlisting and limits implicit reachability. Logging strengthens the control by producing evidence for detections, investigations, and tuning. The checker assigns points for inbound and outbound logging because denied outbound traffic can reveal malware beacons, misconfigurations, and unauthorized tools. Forward logs to a SIEM, retain them for the period required by policy, and alert on denies, policy violations, and administrative changes.

Segmentation, Admin Access, and Patch Recency

Segmentation reduces blast radius by limiting east-west movement between critical zones such as payment, identity, and management networks. Administrative MFA lowers takeover risk, especially for remote management interfaces, APIs, and cloud consoles. Patch recency is scored by days since the last security update, reflecting how quickly known vulnerabilities are closed. Combine this with hardening steps like role-based access, least privilege, and out-of-band management to reduce the likelihood and impact of compromise.

Hygiene Metrics and Report-Ready Outputs

Two practical hygiene signals are unused-rule percentage and the count of externally reachable ports. High stale rule rates inflate complexity and increase the chance of permissive mistakes during urgent changes. Fewer exposed ports generally means smaller attack surface, less noise, and simpler monitoring. After calculation, exportable CSV and PDF summaries capture inputs, scores, and complete breakdowns for audits, risk registers, quarterly reporting, and remediation plans. Use repeat runs to show trendlines and demonstrate control improvement over time.

FAQs

1) What does the compliance score represent?

The score is a weighted 0–100 indicator of firewall governance and exposure controls, based on documentation, reviews, default-deny, logging, change management, segmentation, admin MFA, patch recency, hygiene, and exposed services.

2) Is this a substitute for a formal audit?

No. It is a structured pre-audit check that highlights likely gaps and helps you prioritize evidence collection and remediation before internal or external assessments.

3) How should I estimate unused or stale rules?

Use hit counters, SIEM summaries, or rule analytics. Treat rules unused for 60–90 days as candidates, then confirm with owners before disabling, tightening, or deleting them.

4) What counts as an externally reachable port?

Any TCP or UDP service reachable from the internet or an untrusted network, including through NAT. Validate using external scans, cloud security group reviews, and load balancer listener inventories.

5) How can I improve the score quickly?

Enable default-deny where feasible, turn on bidirectional logging, enforce change tickets, require admin MFA, and run quarterly reviews. Then reduce stale rules and exposed ports with allowlists and secure gateways.

6) Can I align outputs to specific frameworks?

Yes. Choose the closest framework for context, then map each control area to your internal control IDs. Attach the exported CSV or PDF as supporting evidence in your GRC workflow.