I built BTCRouter because most Bitcoin wallets estimate fees with a simple multiplier — "slow / medium / fast" — and it's often catastrophically wrong. When the mempool is empty, you overpay. When it's full, you underpay and wait 3 days. The Problem with Current Fee Estimation Full Bitcoin Core nodes solve this properly, but require: 150GB+ storage All-day initial sync Constant upkeep Too heavy for embedded devices, mobile apps, or quick scripting. BTCRouter uses Blockstream's Electrum API instead — no node required, works from any machine. What BTCRouter Does A Python library for real-time Bitcoin intelligence: Fee Estimation — 4 tiers (economy/normal/fast/instant) from live mempool data Congestion Analysis — score 0–100 of on-chain demand with actionable recommendations UTXO Optimization — greedy selection minimizing inputs + fees RBF Simulation — model Replace-By-Fee scenarios Privacy Scoring — grade your UTXO set based on address reuse and amount patterns How Fee Estimation Works Blockstream returns…