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🌀 3D Spirograph Nebula

Interactive Art & Living Worlds
⛶ Standalone

A true 3D spirograph: torus knots, quantum roses and harmonograph spiros woven into space with perspective, additive glow, phosphor trails, echo interference, an orbiting starfield, gesture orbit and.

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🔊 808 Sub-Bass Note Tuner & Harmonics Designer

Music & Audio
⛶ Standalone

An untuned 808 sub-bass creates mud, phase cancellation, and clashes with your melodic sample. Select your song's root key to find the exact fundamental frequency (Hz), room wavelength standing nod...

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🩸 HbA1c ⇄ Average Glucose

Health & Fitness
⛶ Standalone

Convert HbA1c (%) to estimated average glucose with the NGSP/DCCT formula (eAG mg/dL = 28.7 × A1c − 46.7). Educational only — lab methods differ (IFCC mmol/mol vs NGSP %), and this is not a diagnosis.

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🧪 Split Test Lab

SaaS & Business Killers
⛶ Standalone

The two numbers every experiment platform charges you to see: is this difference real, and how long must the test run? Frequentist z-test with confidence intervals, a proper sample-size and duratio...

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🥃 ABV, Proof & Dilution

Culinary & Food Science
⛶ Standalone

US proof is 2 × ABV%. UK/EU labels use ABV%. Dilute with C₁V₁ = C₂V₂ (alcohol volume conserved). Mixing two bottles uses a weighted average. Not a drink-driving tool.

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♿ Accessible Text Prep

Wellbeing & Community
⛶ Standalone

Paste something you need a specific person to understand — a letter from a council, instructions for an elderly relative, a form your colleague keeps skipping. This rewrites the presentation and th...

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🔊 Ultrasonic Acoustic Levitation

Science & Engineering
⛶ Standalone

40 kHz ultrasonic standing wave acoustic trap. Non-contact levitation of micro-beads and liquid droplets suspended in mid-air at acoustic pressure nodes.

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🌾 Acres ⇄ Hectares ⇄ m²

Science & Engineering
⛶ Standalone

International acre is exactly 4,046.8564224 m²; a hectare is 10,000 m² (a 100 m square). UK land ads mix acres and hectares. Edit any field.

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💆 Acupressure Point Relief Map

Natural Remedies & Herbs
⛶ Standalone

Non-invasive somatic reflexology locator. Guides precise anatomical pressure points for rapid drug-free relief of headaches, nausea, anxiety, and cramps.

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🌱 Adaptogen Synergy Matcher

Natural Remedies & Herbs
⛶ Standalone

HPA-axis endocrine matching engine. Aligns clinical botanical adaptogens to your stress phenotype (high nighttime cortisol vs chronic adrenal exhaustion).

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🧴 Adhesive Selector — Which Glue Sticks This to That?

Home & DIY
⛶ Standalone

Pick the two things you are joining and the conditions it has to survive, and this works out which adhesive will actually hold — with open time, clamp time, full cure and the surface prep that make...

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🏠 Adulting Score Calculator

Productivity & Lifestyle
⛶ Standalone

How well are you really adulting? Take this brutally honest assessment and find out.

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