Compression

Extract a single file from TAR archive by exact path (requires 7zip command)

Compression

Convert TAR archive to 7Z format (requires 7zip command)

Compression

Convert TAR archive to ZIP format (requires 7zip command)

Data Visualization

Generate hierarchical sunburst charts with polar coordinates and radial layout

Development

Generate candidate strings, a CSV template and a local Node.js importer. This website does not create codes in Stripe or track redemptions. Running the importer needs your Stripe API key on your own machine.

Design

Design, preview and export a self-hosted wheel, scratch card or mystery box. Local demos or merchant API results; no hosted prize service.

Document Tools

Turn instructions and local screenshots into annotated guides, printable PDF, standalone HTML and editable project files.

Media

Strip hearing-impaired (SDH) noise from subtitles: bracketed sound effects like [APPLAUSE] and (engine rumbles), speaker labels like JOHN: or NARRATOR -, music-note lines ♪ ♫ — then drop the empty cues left behind.

Media

Render true sidechain compression with FFmpeg’s two-input sidechaincompress: filter the trigger, shape the envelope (attack/release/knee/link/mix), and get the output file plus measured gain reduction.

Converter

Detects, validates and bridges crypto wallet seeds offline: BIP-39 checksum and entropy recovery, SLIP-39 Shamir share parsing with RS1024 checksum and single-group recombination, Electrum v2 version-tag validation and legacy v1 detection — then derives the BIP-32 master xprv/xpub and the first five m/44′/0′/0′/0 addresses, and converts entropy both ways between BIP-39 mnemonics and single-group SLIP-39 share sets.

Science & Education

A complete in-browser formal-verification stack — no cvc5/Z3 binary needed: an SMT-LIB 2.7 script parser for the QF_BV + Bool core with Tseitin bit-blasting of the FixedSizeBitVectors operators (add/sub/mul/udiv/urem, shifts, comparators, concat/extract/extend, ite), an AIGER reader (ASCII aag and binary aig with delta decoding; outputs as bad properties), a BTOR2 reader with word-level bit-blasting, and a hand-written CDCL SAT engine (two-watched literals, VSIDS-style activities, 1-UIP learning, restarts) underneath. On sequential models it runs bounded model checking with counterexample-witness traces, k-induction with unique-state strengthening, McMillan-style Craig interpolation computed from the refutation and independently re-certified by SAT before being trusted, and an IC3/PDR-lite frame loop with predecessor-cube blocking.

Health

Run SIR / SEIR / SEIR+V / SEIR+H ODEs with RK4: R0, herd-immunity threshold, analytic peak and final-size equations, growth-rate conversion, WAIFW next-generation-matrix R0, incidence fitting and intervention simulation.