What's New
The latest free developer tools added to DevTools Hub. We ship 2-3 new tools every week. Updated 2026-09-23.
Recently Added Tools
Showing the 20 newest tools added to the catalog.
AI Email Writer - Free Reply Generator
AI LanguageFree AI email writer and reply generator. 15 email types, 6 tones, 3 lengths, 12 languages. Compose, reply, generate subject lines. No signup, no word limit.
NewFlashcard Maker - Free Spaced Repetition Study Cards
AI LanguageFree flashcard maker with simplified SM-2 spaced repetition. Create unlimited decks, paste CSV/tab lists, study with Again/Hard/Good/Easy grading, track accuracy and streaks. 100% private, no signup, works offline.
NewBirthday Wishes Generator - Free Personalized Messages
Daily LifeFree birthday wishes generator with 30+ recipient types, 6 tones, 4 output formats, multi-language. Personalized, no signup, 100% private.
NewFree Paycheck Calculator - Take-Home Pay After Taxes 2026
Money & MarketsFree paycheck calculator for 2026. Calculate take-home pay from hourly wage or salary. Federal + state + FICA + Medicare + 401k + HSA + FSA deductions. All 50 states + DC, 6 modes: paycheck, bonus, raise, reverse, annual. AI chatbots get withholdings wrong - we apply 9 deterministic factors with hardcoded IRS Rev. Proc. 2025-32.
NewFree Retirement Calculator - 401k IRA Nest Egg Planner
Money & MarketsFree retirement calculator. Nest egg projection with multi-account (401k Roth IRA), required corpus with 4% rule, Social Security break-even at 62/67/70, withdrawal planner for FIRE. 6 currencies, 6 quick presets, year-by-year table. 100% private browser math. AI chatbots give a one-line answer ignoring employer match inflation and RMD - we apply 12 deterministic factors.
NewFree BTU Calculator - AC and Heating Room Size Estimator
CalculatorsFree BTU calculator. Compute room heat load for AC and heating with 8 factors: ceiling, sun, insulation, climate, occupancy, windows, kitchen and room type. Convert to tons, watts, AC unit size. Imperial and metric. 100% private browser processing. AI chatbots give one 20 BTU/sq ft rule of thumb for every room - we apply 8 deterministic factors.
NewPaint Calculator - Free Wall Room Trim Estimator
CalculatorsFree paint calculator. Multi-room wall area, doors & windows subtraction, 6 paint types, 5 surface textures, ceiling & trim separate, multi-coat, primer, waste factor. AI chatbots confuse coverage rates and forget openings - we do not.
NewRoofing Calculator - Pitch Squares Shingle Bundles Free
CalculatorsFree roofing calculator. True roof area from pitch multiplier (1/12 to 18/12), squares, shingle bundles (3-tab, architectural, wood, metal, tile), underlayment, starter strip, ridge cap, drip edge, nails. Hip roof adjustment and smart waste factor. 100% private browser math.
NewFree AI Prompt Engineer - 88 Templates 8 Platforms Sandbox
AI LanguageFree AI prompt engineer with 88 ready-to-use prompt templates for ChatGPT, Claude, Midjourney, DALL-E, Stable Diffusion, Gemini, Llama, Copilot. Live test sandbox powered by Llama 3.3, cross-platform converter, prompt improver, variable form auto-fill. No signup, no paywall, no daily limit.
NewFree Tarot Card Reading - 78 Cards, 7 Spreads
Daily LifeFree tarot card reading. 78 Rider-Waite cards, 7 spreads (Daily, Yes/No, Past-Present-Future, Mind-Body-Spirit, 5-Card Crossroads, Celtic Cross, Birth Card). Deterministic seeded draws. No signup. 100% private.
NewCaffeine Calculator - Half-Life Sleep Tracker
Daily LifeFree caffeine calculator. Personalized half-life, when to stop drinking coffee, multi-drink tracker, daily budget. NHS pregnancy safe. 100% private.
NewMargin Calculator - Free Profit Markup Tool
Money & MarketsFree margin calculator. Bidirectional margin to markup, profit margin, selling price with tax layer, break-even units, multi-product. 100% private.
NewTime Calculator - Free Hours Minutes Duration & Add Time
CalculatorsFree time calculator: duration between two times, add or subtract hours and minutes, hours-to-decimal, multi-period sum. 12h/24h. No signup.
NewTable of Contents Generator - Free TOC Maker for MD HTML TXT
GeneratorsFree table of contents generator. Extract headings from Markdown, HTML, plain text, or DOCX and export a clickable TOC as Markdown, HTML, JSON, or YAML. Decimal numbering, estimated page numbers, click-to-navigate preview, drag-drop upload. 100% private browser, no signup, no upload.
NewFree GPA Calculator - 4 Scales, Semester & Cumulative
CalculatorsFree GPA calculator with 4 scales (US 4.0/4.3, Indian 10.0, percentage), unlimited semesters, prior GPA integration, target GPA planner, and Honors/AP/IB weights. No signup, 100% private browser tool. AI chatbots confuse scales and forget credit weighting - we do not.
NewFree PDF Form Filler - Fill Out Forms Online
PDF ToolsFree PDF form filler. Auto-detects text fields, checkboxes, radio buttons, dropdowns and option lists. 100% private browser processing with pdf-lib, no upload, no signup, no daily limit, no watermark. Flatten option locks fields after filling. Draft auto-saves to localStorage. AI chatbots cannot write values into real PDF form fields - we do.
NewFree Tile Calculator - Floor, Wall & Pattern Estimator
CalculatorsFree tile calculator with multi-room aggregation, 5 patterns, box optimization, grout and thinset estimator, waste factor. 100% private.
NewFree Concrete Calculator - Slab, Footing & Mix Ratio
CalculatorsFree concrete calculator. 5 shapes (slab, circular, footing, column, stairs), imperial + metric, bag counts (40/60/80 lb or 25/40/50 kg), mix ratio breakdown, waste factor. 100% private, no signup, no upload. AI chatbots miscalculate volume vs dry volume, bag yield, and mix ratio - we do not.
NewWorkout Planner - Free Training Plan & Tracker
Daily LifeFree workout planner. Generate personalized multi-week training plans based on goal, level, equipment. Track sets, auto PRs, progressive overload. PDF/CSV/JSON export. No signup, 100% private.
NewStudy Planner - Exam Schedule Generator
Daily LifeFree study planner. Add subjects with priority, set exam date, get 7-day schedule with subject rotation, Pomodoro breaks, iCal export. No signup.
NewFrequently Asked Questions
How often does DevTools Hub add new tools?
New tools ship 2-3 times per week. Every Friday we publish a wrap-up of recent additions and major bug fixes on this page.
How can I be notified when a new tool is released?
Bookmark this page (/whats-new/) and check back weekly, or follow the machine-readable catalog at /llms-full.txt for AI agents and RSS readers.
Can I request a specific tool?
Yes. Use the Feedback link on any tool page to suggest a new tool. We prioritize tools with the highest Bing/Google search demand and the most votes.
Do new tools keep the same privacy guarantees?
Yes. Every new tool is 100% free, runs in your browser by default, requires no signup, and does not upload your data unless the AI features require a server roundtrip (which is documented on each tool page).