A small collection of browser-based utilities and open resources for FPGA and DSP work. The calculators run entirely in your browser — nothing you type is sent to a server.
Browser-only tools — no install, no sign-in, no data leaves your machine.
Fixed-point calculator — convert decimal / hex / binary values into a
Q-format fixed-point representation (bits, hex, raw integer, float), and run
add / subtract / multiply / multiply-accumulate with full control over rounding
and overflow. Bit-exact to the fxpmath-verified reference.
IEEE-754 float converter — convert decimal ⇄ bits ⇄ hex for binary16 /
binary32 / binary64, see the sign / exponent / mantissa decomposition and special
cases (NaN, ±Inf, subnormal, ±0), and get the VHDL std_logic_vector
literal. Native browser IEEE-754.
Open-source building blocks behind our tools, free to use in your own projects — browse them all in our Open Source section.
lm_math_fi — a zero-dependency fixed-point math library (Python model + a
JavaScript port), verified bit-for-bit against fxpmath. The fixed-point
calculator is powered by the JavaScript port.
lm_math_float — Apache-2.0 VHDL floating-point RTL (IEEE-754 arithmetic cores for FPGA). Synthesizable building blocks for hardware float pipelines.
Authoritative references on fixed-point and Q-format arithmetic.
Q (number format) — Wikipedia — the notation and the integer/fractional split.
Fixed-point arithmetic — Wikipedia — overflow, rounding and scaling fundamentals.
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