NetEng Sidekick: Subnet Calculator icon

NetEng Sidekick: Subnet Calculator

by june.coffee · Developer Tools
Manifest V3 Free
View in Chrome Web Store Data as of 16 Oct 2026

Professional IPv4/IPv6 Subnet Calculator. Supports CIDR, Export, and VLSM.

Users
30
+7 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
1
0 in 30 days
Store rank
#130K
#109K among extensions
Version
1.4.2
updated 9 Dec 2025

Users

monthly, 11 months
01530Dec 2025Jun 2026Oct 2026
Latest, 16 Oct 2026: 30 usersMove the mouse over the chart for any month

Ratings count

monthly, 11 months
001Dec 2025Jun 2026Oct 2026
Latest, 16 Oct 2026: 1 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About NetEng Sidekick: Subnet Calculator

NetEng Sidekick - Offline Subnet Calculator 🛑 Stop switching tabs during critical maintenance windows. 🖥️ Created by a network engineer for network engineers. NetEng Sidekick is the workflow accelerator designed specifically for Wired and Wireless Network Engineers, Sysadmins, and Cloud Architects. It moves the subnet calculator from a browser tab to a permanent Side Panel—keeping your calculations visible while you configure Wireless LAN Controllers, audit Firewall ACLs, or design Cloud VPCs. 🚀 Why this is your new favorite tool: 1. Always-On Side Panel 🖥️ Never lose your place again. Whether you are scrolling through a Cisco CLI session in a browser terminal or reading Azure documentation, your calculator stays open and ready on the right side of your screen. 2. Serious IPv6 Power 🌐 IPv6 isn't the future; it's the now. While other calculators fail at 128-bit math, NetEng Sidekick handles full IPv6 precision. Calculate Prefix Delegations for ISP handoffs. Visualize /64 breakdowns for IoT VLANs. Get accurate Range Start/End for massive address blocks without crashing your browser. 3. Smart Input (Cisco & Legacy Friendly) 🧠 We know the real world isn't always CIDR. Paste standard CIDR: 192.168.10.1/24 Paste legacy masks: 192.168.10.1 255.255.255.0 We handle both automatically. No toggles required. 4. Visual VLSM Breakdown 🍰 Need to carve up a /24 Management VLAN into smaller chunks for different building wings? Select your new mask size (e.g., /27). Instantly see a table of every available subnet. Click to copy the Network ID or Broadcast address instantly. 5. One-Click Efficiency ⚡ Every result is clickable. Copy the First Usable IP for your Gateway configuration or the Wildcard Mask for your OSPF config with a single click. 6. Export for Documentation 📄 [NEW] Done with your design? Export your calculation results to a .txt file instantly. Perfect for attaching to Change Management requests, Jira tickets, or saving to your project documentation folder. 🛠️ Built for the Daily Life of a Network Engineer WIRELESS ENGINEERS: Quickly calculate subnet sizes for Guest WiFi pools to ensure you don't run out of DHCP leases during peak hours. Verify AP Management subnets when deploying new controllers. WIRED ENGINEERS: Rapidly verify if a specific IP falls inside a Summary Route or ACL object group without leaving your monitoring dashboard. SECURITY TEAMS: Double-check CIDR ranges when whitelisting IP blocks in your WAF or Firewall to prevent accidental over-exposure. NETWORK ARCHITECTS: Plan complex VLSM schemas and export the plan to text files to share with the implementation team. 🔒 Privacy First 100% Client-Side: No data ever leaves your browser. Offline Ready: Works perfectly in air-gapped environments or when the internet is down (which is usually when you need it most!). Upgrade your workflow today. Add NetEng Sidekick to Chrome.

Growth

WindowUsersChangeRatingsRating
7 days+2+7.1%00.00
30 days+7+30.4%00.00
6 months+12+66.7%00.00

Version history

2 versions recorded
1.4.29 Dec 2025
1.4.13 Dec 2025

Details

Category
Developer Tools
First seen
3 Dec 2025
Size
18 KB
Languages
en
Pricing
Free
Extension ID
lcmpkgcidgefhlamnlpdgclbbdnlpiak

Permissions and risk

Minimal riskimpact 0, likelihood 2
Permissions
sidePanel

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