Sindri

Endpoints (64 live)

• POST /regexTest — Tests a regular expression pattern against a string, guarded against catastrophic backtracking (ReDoS) by running the match in an isolated worker thread with a hard 500ms timeout that fails closed. (0.01 USDC on Solana)
• POST /baristaFireCalculator — Barista FIRE calculator. Simulates net worth growth through a full-time-saving phase and then a reduced-target phase funded partly by part-time/side income after quitting full-time work, until full financial independence is reached. (0.01 USDC on Base)
• POST /unitConvertScientific — Scientific unit conversion for pressure, energy, and molarity using exact conversion factors. (0.01 USDC on Solana)
• POST /alcoholSavingsCalculator — Alcohol spending and opportunity-cost calculator. Sums home and going-out drinking costs plus associated rideshare costs into monthly and yearly totals, then projects what that redirected spending could grow into if invested instead, using the future-value-of-an-annuity formula. (0.01 USDC on Solana)
• POST /base64Encode — Base64 encoder API. Encodes UTF-8 text to base64 instantly and correctly — skip burning agent tokens hand-computing base64, which LLMs frequently get wrong on padding and edge cases. (0.01 USDC on Base)
• POST /capRateCalculator — Cap rate calculator for real estate investing. Runs a full multi-year deal analysis (per-category rent/expense growth, a sale scenario, IRR) and headlines the capitalization rate: first-year NOI divided by purchase price. (0.01 USDC on Solana)
• POST /diffText — Line-based diff between two strings using the Myers diff algorithm (via the diff/jsdiff library), returning a list of equal/add/remove operations. (0.01 USDC on Base)
• POST /chemicalElementLookup — Periodic table element lookup by symbol or atomic number, returning name, atomic mass, and category. Covers the most commonly referenced elements. (0.01 USDC on Base)
• POST /base64Decode — Base64 decoder API. Decodes a base64 string back to UTF-8 text instantly and correctly, avoiding the padding and charset errors LLMs make when decoding base64 by hand. (0.01 USDC on Base)
• POST /astronomyEphemeris — Sunrise, sunset, solar noon, day length, and moon phase for a given latitude/longitude/date, computed via the suncalc library (standard solar/lunar position algorithms) — precise astronomical math an LLM cannot reliably compute mentally. (0.01 USDC on Solana)
• POST /isEmail — Email validation API. Checks whether a string is a syntactically valid email address using the same production-grade validation library trusted across the Node.js ecosystem, catching edge cases a quick regex misses. Returns true or false. (0.01 USDC on Solana)
• POST /cashOnCashReturnCalculator — Cash-on-cash return calculator for real estate investing. Runs a full multi-year deal analysis (per-category rent/expense growth, a sale scenario, IRR) and headlines the first-year cash-on-cash return: operating cash flow divided by invested cash. (0.01 USDC on Base)
• POST /isURL — URL validation API. Checks whether a string is a syntactically valid URL, catching malformed schemes, hosts, and encoding edge cases a naive check misses. Returns true or false. (0.01 USDC on Base)
• POST /bigNumberArithmetic — Arbitrary-precision integer arithmetic (add, subtract, multiply, power) beyond IEEE-754 float precision, using native BigInt. Operands are passed as digit strings so precision is never lost in transit. For power, the combined magnitude (base digit count x exponent) is capped at 50000 to bound response size, in addition to the per-operand digit cap and exponent cap. (0.01 USDC on Base)
• POST /coastFireCalculator — Coast FIRE calculator. Computes the lump sum needed today, invested with zero further contributions, to grow into your full retirement number by your target retirement age, plus (given an ongoing monthly contribution) a year-by-year projection of when your actual trajectory crosses that lump sum. (0.01 USDC on Base)
• POST /mortgageComparisonCalculator — 15-year vs 30-year mortgage comparison calculator. Computes monthly payment and total interest for both loan terms on the same purchase price and down payment, and reports the payment and lifetime-interest tradeoff between them. (0.01 USDC on Base)
• POST /matrixOperations — Matrix operations: multiply, transpose, determinant, and invert, for matrices up to 20x20. Uses the ml-matrix library's LU decomposition (LuDecomposition) for determinant and inversion, with a numerical near-singularity guard beyond the library's exact-singular check. (0.01 USDC on Solana)
• POST /generateInternetData — Network-format generator API. Generates a valid ipv4/ipv6 address (optionally within a CIDR block or named network range) or a well-formed JWT string (via one of: ipv4, ipv6, jwt). Accepts optional locale (default en_US). jwt header/payload objects are capped to 2000 serialized characters. (0.01 USDC on Base)
• POST /keepingUpWithInflationCalculator — Keeping up with inflation calculator. Computes the pre-tax raise needed under two scenarios — keeping the same dollar amount saved, or maintaining the same savings rate — after inflation raises your spending and a marginal tax rate reduces the raise itself. (0.01 USDC on Base)
• POST /jwtDecode — Decodes (does not verify) a JWT by base64url-decoding its header and payload segments. Signature validity is never checked — do not use this to authenticate a token. (0.01 USDC on Base)

+44 more endpoints.