What developer tools does Texterfly offer?

Texterfly offers 10 free developer tools: a JSON Formatter & Validator, an All-in-One Data Converter (JSON/CSV/XML/YAML), a JWT Decoder & Analyzer, a Cron Job Generator & Explainer, a QR Code Generator, a Password Generator, a Unix Timestamp Converter, a Lorem Ipsum Generator, an Interactive Data Visualization Builder, and a CSS Neumorphism Generator. All are free, browser-based, and require no signup.

How do I format and validate JSON online?

Paste your JSON into the JSON Formatter & Validator tool. It automatically detects syntax errors with precise line and column numbers, beautifies the output with proper indentation, and offers a minify option to compress the JSON for production use. You can also upload a .json file or fetch JSON from a URL.

How do I convert JSON to CSV (or CSV to JSON)?

Use the All-in-One Data Converter & Formatter. Paste your JSON or CSV, select the output format, and the conversion happens instantly. The tool also supports XML and YAML conversion, file upload, URL fetching, and JSONPath queries for extracting specific fields before converting.

How do I decode a JWT token?

Paste your JWT into the JWT Decoder & Analyzer. The tool instantly splits it into the header, payload, and signature sections, decodes the base64url encoding, checks expiration (exp claim), and detects common security issues like the "none" algorithm attack. For HS256 tokens, you can enter a secret key to verify the signature.

How do I write a cron job expression?

A cron expression has five fields: minute (0-59), hour (0-23), day of month (1-31), month (1-12), and day of week (0-7). Examples: "0 9 * * 1" runs every Monday at 9 AM; "0 0 * * *" runs daily at midnight; "*/15 * * * *" runs every 15 minutes. Use the Cron Job Generator to build and validate expressions visually with a real-time English translation.

What makes a password strong?

A strong password has: at least 16 characters (longer is better), a mix of uppercase and lowercase letters, numbers, and symbols, no dictionary words or predictable patterns, and is unique (never reused across accounts). The Password Generator creates cryptographically random passwords meeting all these criteria and shows an entropy-based strength score.

What is a Unix timestamp?

A Unix timestamp is the number of seconds elapsed since January 1, 1970, 00:00:00 UTC (the Unix Epoch). It is the universal standard for representing time in computing. A 10-digit number is seconds; 13 digits is milliseconds; 16 digits is microseconds; 19 digits is nanoseconds. Use the Timestamp Converter to convert between Unix time and human-readable dates.

What is neumorphism in CSS?

Neumorphism (also called Soft UI) is a design style that uses a combination of two box shadows — one light and one dark — on a background that matches the element's color to create a soft, extruded or pressed appearance. The CSS Neumorphism Generator creates the exact box-shadow CSS code for any color, size, and depth with a live preview.

What is the structure of a JWT?

A JWT (JSON Web Token) consists of three base64url-encoded parts separated by dots: Header.Payload.Signature. The Header specifies the token type (JWT) and signing algorithm (e.g. HS256). The Payload contains claims — statements about the user or session like "sub" (subject), "exp" (expiration), "iat" (issued at), and "iss" (issuer). The Signature verifies that the token was not tampered with.

Are these developer tools free?

Yes. All 10 developer tools on Texterfly are 100% free with no registration, subscription, or payment required.

Is my code or data private?

Yes. All processing runs entirely in your browser using JavaScript. Your JSON, JWT tokens, passwords, and data are never sent to any server or stored anywhere. This makes the tools safe for sensitive tokens, credentials, and confidential data.

Can I use these tools for commercial projects?

Yes. All Texterfly developer tools are free for both personal and commercial use. There are no licensing restrictions on how you use the output.

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Subnet Calculator

Calculate network address, broadcast address, usable host range, and subnet mask from any CIDR notation. Free, instant, no sign-up.

IP & CIDR

IP Address

CIDR Prefix/24

Subnet Mask

Class CPrivate

Network

192.168.1.0/24

256

Total IPs

254

Usable Hosts

192.168.1.1

First Host

192.168.1.254

Last Host

Details

Network Address

192.168.1.0

Broadcast Address

192.168.1.255

Subnet Mask

255.255.255.0

Wildcard Mask

0.0.0.255

Usable Host Range

192.168.1.1 – 192.168.1.254

CIDR Notation

192.168.1.0/24

Binary

IP Address11000000.10101000.00000001.00001010

Subnet Mask11111111.11111111.11111111.00000000

Network11000000.10101000.00000001.00000000

Split Into Subnets

Number of subnets

Rounded up to 4 subnets of /26 each (64 addresses per subnet).

#	Network	Usable Range
1	192.168.1.0/26	192.168.1.1 – 192.168.1.62
2	192.168.1.64/26	192.168.1.65 – 192.168.1.126
3	192.168.1.128/26	192.168.1.129 – 192.168.1.190
4	192.168.1.192/26	192.168.1.193 – 192.168.1.254

100% client-side — nothing you enter here is sent to a server.

CIDR Quick-Reference Chart

Every common prefix from /8 to /32, with its subnet mask and host counts.

CIDR	Subnet Mask	Total IPs	Usable Hosts
/8	255.0.0.0	16,777,216	16,777,214
/9	255.128.0.0	8,388,608	8,388,606
/10	255.192.0.0	4,194,304	4,194,302
/11	255.224.0.0	2,097,152	2,097,150
/12	255.240.0.0	1,048,576	1,048,574
/13	255.248.0.0	524,288	524,286
/14	255.252.0.0	262,144	262,142
/15	255.254.0.0	131,072	131,070
/16	255.255.0.0	65,536	65,534
/17	255.255.128.0	32,768	32,766
/18	255.255.192.0	16,384	16,382
/19	255.255.224.0	8,192	8,190
/20	255.255.240.0	4,096	4,094
/21	255.255.248.0	2,048	2,046
/22	255.255.252.0	1,024	1,022
/23	255.255.254.0	512	510
/24	255.255.255.0	256	254
/25	255.255.255.128	128	126
/26	255.255.255.192	64	62
/27	255.255.255.224	32	30
/28	255.255.255.240	16	14
/29	255.255.255.248	8	6
/30	255.255.255.252	4	2
/31	255.255.255.254	2	2
/32	255.255.255.255	1	1

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Free IP Subnet & CIDR Calculator

Subnetting math is simple in theory — it's all binary AND/OR operations — but easy to get wrong by hand, especially with edge cases like /31 point-to-point links or /32 host routes. This calculator handles the full range from /0 to /32 correctly, converts between CIDR prefix and dotted-decimal subnet mask in either direction, and works out the network address, broadcast address, and usable host range instantly.

How Subnet Calculations Work

🌐 Network Address

The IP address with every host bit set to 0 — found by ANDing the IP address with the subnet mask.

📡 Broadcast Address

The IP address with every host bit set to 1 — found by ORing the network address with the wildcard mask (the inverted subnet mask).

👥 Usable Hosts

Every address in the range except the network and broadcast addresses — calculated as 2^(host bits) − 2 for most subnets.

🔀 CIDR Prefix

The number of leading 1 bits in the subnet mask — a /24 mask (255.255.255.0) has 24 leading 1 bits, leaving 8 bits for hosts.

Special Cases: /31 and /32

Most subnets reserve their first address (network) and last address (broadcast), leaving the rest usable. Two prefixes break that pattern: a /32 identifies exactly one host with no network or broadcast concept at all, and a /31, defined by RFC 3021, is used almost exclusively for point-to-point links — both of its two addresses are usable, since there's no need for a broadcast address on a link with only two endpoints. This calculator applies those rules automatically rather than always subtracting two hosts.

Frequently Asked Questions

What is CIDR notation?

CIDR (Classless Inter-Domain Routing) notation combines an IP address with a slash and a number, like 192.168.1.0/24, where the number is how many leading bits of the address are the fixed network portion — the rest identify hosts within that network.

How do I calculate the number of usable hosts in a subnet?

Usable hosts is 2^(32 − prefix length) − 2 for most subnets, since the first address is reserved as the network address and the last as the broadcast address. A /24 has 2^8 − 2 = 254 usable hosts. /31 and /32 are special cases with their own rules.

What's different about a /31 or /32 subnet?

A /32 identifies a single host with no network or broadcast concept. A /31, per RFC 3021, is used for point-to-point links and has no reserved network or broadcast address — both of its two addresses are usable.

How is the broadcast address calculated?

The broadcast address is the network address with every host bit set to 1 — equivalent to the network address OR'd with the wildcard mask (the inverse of the subnet mask).

What's the difference between a public and private IP address?

Private IP addresses (like 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16) are reserved for use inside local networks and aren't routable on the public internet. Any address outside those reserved ranges (and outside loopback and link-local ranges) is considered a public, internet-routable address.

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