These calculators handle the unit conversions and layout math that developers reach for most. Subnet IP address ranges with the IPv4 Subnet Calculator, convert storage values with the Byte Conversion Calculator, switch between REM and PX for responsive CSS, translate RGB to CMYK for print workflows, and compute Pixels per Inch (PPI) or Aspect Ratio for any display or design asset.
Browse the most-used tools in the ranked list, or flip to the Trending tab to see what other developers are looking up right now. Every calculator is free, requires no account, and works on any device.
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SHA-256 Hash CalculatorFree SHA-256 hash calculator. Enter any text and get its 256-bit SHA-2 digest as a 64-character hexadecimal string, plus the UTF-8 byte length.
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MD5 Hash CalculatorFree MD5 hash calculator. Compute the 128-bit MD5 (RFC 1321) digest of any text as a 32-character hex string, with UTF-8 byte and character counts.
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CRC Checksum CalculatorCompute CRC-8, CRC-16/CCITT-FALSE, and CRC-32 (IEEE) checksums from ASCII text. Get the cyclic redundancy check value in hex and decimal instantly.
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Hex to RGB Color ConverterConvert any hex color code (#RRGGBB or #RGB) to its RGB values instantly. See the red, green and blue channels plus a live color swatch.
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Precision and Recall CalculatorCalculate precision, recall and F1 score from true positives, false positives and false negatives. Free classification metrics calculator.
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Number Base ConverterConvert numbers between binary, octal, decimal, and hexadecimal instantly. Free online base converter with step-by-step decimal value shown.
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IP Broadcast / Network Address CalculatorCalculate network address, broadcast address, subnet mask, usable host range and host count from any IPv4 address and CIDR prefix length.
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Video Bitrate CalculatorCalculate video bitrate from file size and duration, or estimate file size from a target bitrate. Convert between Mbps, kbps and MB instantly.
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IEEE 754 Floating Point ConverterConvert a 32-bit hex value to its IEEE 754 single-precision decimal float. See the sign, exponent, and mantissa breakdown instantly.
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FPS to Frame Time (ms) CalculatorConvert frames per second (FPS) to frame time in milliseconds instantly. Find how many ms each frame takes at 30, 60, 120, 144 FPS and more.
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HSL to Hex Color ConverterConvert any HSL color (hue, saturation, lightness) into a hex code and RGB values instantly. Free online HSL → Hex converter with a live color preview.
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ASCII to Binary ConverterConvert any text to binary instantly. Each character becomes its ASCII code as an 8-bit binary number, concatenated into a full binary string.
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Data Storage Unit ConverterConvert data storage units between Bytes, KB, MB, GB and TB using binary (1024) conversion. Fast, accurate digital storage size converter.
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Binary to Octal ConverterConvert any binary number (base 2) to octal (base 8) instantly. Free online binary-to-octal converter that also shows the decimal value and step grouping.
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Text to Base64 EncoderFree online Base64 encoder. Convert any text or UTF-8 string to Base64 instantly. See input byte count, output length, and learn how Base64 works.
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Base64 to Text DecoderFree Base64 decoder. Paste any Base64 string to instantly convert it back to plain text, with decoded byte count and padding details shown.
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CIDR to Subnet Mask ConverterConvert a CIDR prefix (/24, /16, etc.) to a dotted-decimal subnet mask instantly. See total addresses and usable hosts for any IPv4 prefix length 0–32.
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URL Encode / Decode CalculatorEncode or decode text using RFC 3986 percent-encoding. Convert unsafe characters to %XX hex bytes and reverse them back instantly.
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Unix Timestamp Calculator (Seconds & Milliseconds)Convert a Unix time in milliseconds to seconds, minutes and days since the epoch. Free Unix timestamp calculator with the exact floor formula explained.
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Octal to Binary ConverterConvert any octal (base 8) number to binary (base 2) instantly. Each octal digit maps to 3 binary bits. Free, accurate, with worked examples.
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Base Converter CalculatorConvert numbers between any bases from 2 to 36 — binary, octal, decimal, hexadecimal and more. Shows the decimal value and the converted result instantly.
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Random UUID Generator (v4)Generate random version 4 UUIDs instantly. Create 1-50 RFC 4122 compliant UUIDs with options for case and hyphens. Free online UUID generator.
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GB to TB ConverterConvert gigabytes (GB) to terabytes (TB) instantly. Choose binary (1024) or decimal (1000) standard for accurate storage capacity conversion.
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KB to MB ConverterConvert kilobytes (KB) to megabytes (MB) instantly. Choose binary (1024) or decimal (1000) standard for accurate file size conversions.
Frequently asked questions
What developer calculations are covered here?
You can calculate IPv4 subnets — network address, broadcast, host range, and CIDR mask — convert storage units from bits to terabytes, switch between REM and PX for any root font size, translate RGB to CMYK, compute PPI for monitors and screens, and determine aspect ratios for video or UI design work.
How accurate are the results?
These tools use deterministic formulas — binary subnet math, exact storage unit multipliers, and the CSS specification's defined REM-to-PX relationship — so outputs are precise for the values you enter. For production networking or print work, double-check critical values against your OS subnet tool, CSS spec, or color profile documentation before deploying.
Are these tools free?
Yes. Every tool is free with no login, subscription, or account required. Enter a subnet range, font size, resolution, or color value and get your result immediately on any device.
Do you store IP addresses, color codes, or other data I enter?
No. All calculations run entirely in your browser. We never collect, log, or transmit any IP addresses, pixel values, color codes, or other developer data you enter — everything stays on your device.
Which developer tools here are the most popular?
The list is ordered by real visitor usage, so the tools at the top are what developers reach for most. Check the Trending tab to see which calculators are rising in popularity lately, or Recently Added to find the latest tools in this category.
