diff --git a/calculators_list.md b/calculators_list.md
index ecddd20..0a0caea 100644
--- a/calculators_list.md
+++ b/calculators_list.md
@@ -1589,6 +1589,36 @@ The registry currently contains 1333 unique calculator slugs.
 | Calories to BTU – Compare calories to BTUs when juggling cooking and heating. | calories-to-btu | 0.0039656667 |
 | Calories to Kilocalories – Switch food calories into dietary kilocalories. | calories-to-kilocalories | 0.001 |
 | Calories to Watt-hours – Express small calorie amounts as watt-hours. | calories-to-watt-hours | 0.0011622222222222222 |
+| Thermal expansion coefficient (per °C) to per °F – Convert metric expansion rates into Fahrenheit increments. | thermal-expansion-coefficient-per-c-to-per-f | temperature | 0.5555555556 |
+| Thermal expansion coefficient (per °F) to per °C – Return Fahrenheit expansion rates back into Celsius units. | thermal-expansion-coefficient-per-f-to-per-c | temperature | 1.8 |
+| Thermal expansion coefficient (per °C) to per °K – Celsius and Kelvin intervals match, so the coefficient stays the same. | thermal-expansion-coefficient-per-c-to-per-k | temperature | 1.0 |
+| Thermal expansion coefficient (per °K) to per °C – Kelvin and Celsius increments are identical so the coefficient remains unchanged. | thermal-expansion-coefficient-per-k-to-per-c | temperature | 1.0 |
+| Thermal expansion coefficient (per °F) to per °R – Fahrenheit and Rankine temperature steps are the same, so the coefficient stays constant. | thermal-expansion-coefficient-per-f-to-per-r | temperature | 1.0 |
+| Thermal expansion coefficient (per °R) to per °F – Convert Rankine expansion rates back into Fahrenheit scales. | thermal-expansion-coefficient-per-r-to-per-f | temperature | 1.0 |
+| Thermal resistance (K/W) to °F·hour/BTU – Express conductive resistance in inch-pound-friendly units. | thermal-resistance-k-per-watt-to-fahrenheit-hour-btu | other | 0.5275279263 |
+| Thermal resistance (°F·hour/BTU) to K/W – Go back to SI resistance units from imperial BTU-based values. | thermal-resistance-fahrenheit-hour-btu-to-k-per-watt | other | 1.8956342406 |
+| Thermal conductivity (W/(m·K)) to BTU/(hr·ft·°F) – Swap metric conductivity into BTU-foot systems for insulation tables. | thermal-conductivity-w-per-meter-k-to-btu-per-hour-foot-fahrenheit | other | 0.5777893165 |
+| Thermal conductivity (BTU/(hr·ft·°F)) to W/(m·K) – Return imperial conductivity values to SI. | thermal-conductivity-btu-per-hour-foot-fahrenheit-to-w-per-meter-k | other | 1.7313441288 |
+| Specific heat capacity (J/(kg·K)) to cal/(g·°C) – Switch joules per kilogram into calories per gram. | specific-heat-j-per-kg-k-to-cal-per-gram-c | energy | 0.0002390057 |
+| Specific heat capacity (cal/(g·°C)) to J/(kg·K) – Express calories per gram as joules per kilogram. | specific-heat-cal-per-gram-c-to-j-per-kg-k | energy | 4184.0 |
+| Specific heat capacity (J/(kg·K)) to Btu/(lb·°F) – Relate SI heat capacity to imperial Btu per pound-degree. | specific-heat-j-per-kg-k-to-btu-per-pound-f | energy | 0.0011608773 |
+| Specific heat capacity (Btu/(lb·°F)) to J/(kg·K) – Return imperial values to metric Joule units. | specific-heat-btu-per-pound-f-to-j-per-kg-k | energy | 861.4175127 |
+| Specific heat capacity (J/(kg·K)) to kJ/(kg·K) – Move the metric values up to kilojoules. | specific-heat-j-per-kg-k-to-kj-per-kg-k | energy | 0.001 |
+| Specific heat capacity (kJ/(kg·K)) to J/(kg·K) – Drop kilojoules back to joules. | specific-heat-kj-per-kg-k-to-j-per-kg-k | energy | 1000.0 |
+| Volumetric heat capacity (J/(m³·K)) to Btu/(ft³·°F) – Convert SI volumetric capacity into familiar English units. | volumetric-heat-capacity-j-per-cubic-meter-k-to-btu-per-cubic-foot-f | energy | 0.0000149107 |
+| Volumetric heat capacity (Btu/(ft³·°F)) to J/(m³·K) – Return to SI volumetric heat values. | volumetric-heat-capacity-btu-per-cubic-foot-f-to-j-per-cubic-meter-k | energy | 67066.1024763 |
+| Volumetric heat capacity (J/(m³·K)) to kJ/(m³·K) – Raise SI volumetric capacity into kilojoule scale. | volumetric-heat-capacity-j-per-cubic-meter-k-to-kj-per-cubic-meter-k | energy | 0.001 |
+| Volumetric heat capacity (kJ/(m³·K)) to J/(m³·K) – Shrink kilojoule-based volumetric capacities back into joules. | volumetric-heat-capacity-kj-per-cubic-meter-k-to-j-per-cubic-meter-k | energy | 1000.0 |
+| Thermal conductivity (W/(m·K)) to cal/(cm·s·°C) – Switch metric conductivity into caloric units per centimeter per second. | thermal-conductivity-w-per-meter-k-to-cal-per-centimeter-second-c | other | 0.0023900574 |
+| Thermal conductivity (cal/(cm·s·°C)) to W/(m·K) – Convert the caloric format back into SI watts per meter per Kelvin. | thermal-conductivity-cal-per-centimeter-second-c-to-w-per-meter-k | other | 418.4 |
+| Heat flux density (W/m²) to BTU/(hr·ft²) – Translate metric heat flux onto imperial area units. | heat-flux-density-w-per-square-meter-to-btu-per-hour-square-foot | energy | 0.3169983306 |
+| Heat flux density (BTU/(hr·ft²)) to W/m² – Turn imperial heat flux back into SI watts per square meter. | heat-flux-density-btu-per-hour-square-foot-to-w-per-square-meter | energy | 3.1545907453 |
+| Heat flux density (W/m²) to W/ft² – Convert metric heat flux into square-foot units. | heat-flux-density-w-per-square-meter-to-w-per-square-foot | energy | 0.09290304 |
+| Heat flux density (W/ft²) to W/m² – Translate square-foot flux back into square meters. | heat-flux-density-w-per-square-foot-to-w-per-square-meter | energy | 10.763910417 |
+| Heat transfer coefficient (W/(m²·K)) to BTU/(hr·ft²·°F) – Express SI convective coefficients in imperial units. | heat-transfer-coefficient-w-per-square-meter-k-to-btu-per-hour-square-foot-f | energy | 0.1761101837 |
+| Heat transfer coefficient (BTU/(hr·ft²·°F)) to W/(m²·K) – Return imperial coefficients back into SI. | heat-transfer-coefficient-btu-per-hour-square-foot-f-to-w-per-square-meter-k | energy | 5.6782633415 |
+| Heat transfer coefficient (W/(m²·K)) to W/(ft²·°F) – Move the conduction coefficient into mixed-area and temperature units. | heat-transfer-coefficient-w-per-square-meter-k-to-w-per-square-foot-f | energy | 0.0516128 |
+| Heat transfer coefficient (W/(ft²·°F)) to W/(m²·K) – Convert the mixed imperial SI coefficient back into its base units. | heat-transfer-coefficient-w-per-square-foot-f-to-w-per-square-meter-k | energy | 19.3750387506 |
 | Carats to Milligrams – Show gemstone carats as milligrams for lab records. | carats-to-milligrams | 200 |
 | Celsius to Delisle – Flip Celsius into the Delisle scale for historical references. | celsius-to-delisle | Linear Offset (-1.5x + 150) |
 | Celsius to Kelvin – Add the offset to move from Celsius into Kelvin. | celsius-to-kelvin | Linear Offset (1x + 273.15) |
diff --git a/hdyc-svelte/src/lib/data/calculators.ts b/hdyc-svelte/src/lib/data/calculators.ts
index dfb7143..2b8664f 100644
--- a/hdyc-svelte/src/lib/data/calculators.ts
+++ b/hdyc-svelte/src/lib/data/calculators.ts
@@ -1526,6 +1526,36 @@ export const calculators: CalculatorDef[] = [
   {"slug": "short-tons-to-long-tons", "name": "Short Tons to Long Tons", "category": "weight", "type": "standard", "teaser": "Express short tons as long tons.", "labels": {"in1": "Short Tons", "in2": "Long Tons"}, "factor": 0.892857, "hidden": true},
   {"slug": "short-tons-to-metric-tons", "name": "Short Tons to Metric Tons", "category": "weight", "type": "standard", "teaser": "Convert short tons into metric tons.", "labels": {"in1": "Short Tons", "in2": "Metric Tons"}, "factor": 0.90718474, "hidden": true},
   {"slug": "sidereal-days-to-solar-days", "name": "Sidereal days to Solar days", "category": "time", "type": "standard", "teaser": "Compare a sidereal day with a solar day.", "labels": {"in1": "Sidereal days", "in2": "Solar days"}, "factor": 0.9972695669},
+  {"slug": "thermal-expansion-coefficient-per-c-to-per-f", "name": "Thermal expansion coefficient (per \u00b0C) to per \u00b0F", "category": "temperature", "type": "standard", "teaser": "Convert metric expansion rates into Fahrenheit increments.", "labels": {"in1": "Thermal expansion coefficient (per \u00b0C)", "in2": "per \u00b0F"}, "factor": 0.5555555556},
+  {"slug": "thermal-expansion-coefficient-per-f-to-per-c", "name": "Thermal expansion coefficient (per \u00b0F) to per \u00b0C", "category": "temperature", "type": "standard", "teaser": "Return Fahrenheit expansion rates back into Celsius units.", "labels": {"in1": "Thermal expansion coefficient (per \u00b0F)", "in2": "per \u00b0C"}, "factor": 1.8},
+  {"slug": "thermal-expansion-coefficient-per-c-to-per-k", "name": "Thermal expansion coefficient (per \u00b0C) to per \u00b0K", "category": "temperature", "type": "standard", "teaser": "Celsius and Kelvin intervals match, so the coefficient stays the same.", "labels": {"in1": "Thermal expansion coefficient (per \u00b0C)", "in2": "per \u00b0K"}, "factor": 1.0},
+  {"slug": "thermal-expansion-coefficient-per-k-to-per-c", "name": "Thermal expansion coefficient (per \u00b0K) to per \u00b0C", "category": "temperature", "type": "standard", "teaser": "Kelvin and Celsius increments are identical so the coefficient remains unchanged.", "labels": {"in1": "Thermal expansion coefficient (per \u00b0K)", "in2": "per \u00b0C"}, "factor": 1.0},
+  {"slug": "thermal-expansion-coefficient-per-f-to-per-r", "name": "Thermal expansion coefficient (per \u00b0F) to per \u00b0R", "category": "temperature", "type": "standard", "teaser": "Fahrenheit and Rankine temperature steps are the same, so the coefficient stays constant.", "labels": {"in1": "Thermal expansion coefficient (per \u00b0F)", "in2": "per \u00b0R"}, "factor": 1.0},
+  {"slug": "thermal-expansion-coefficient-per-r-to-per-f", "name": "Thermal expansion coefficient (per \u00b0R) to per \u00b0F", "category": "temperature", "type": "standard", "teaser": "Convert Rankine expansion rates back into Fahrenheit scales.", "labels": {"in1": "Thermal expansion coefficient (per \u00b0R)", "in2": "per \u00b0F"}, "factor": 1.0},
+  {"slug": "thermal-resistance-k-per-watt-to-fahrenheit-hour-btu", "name": "Thermal resistance (K/W) to \u00b0F\u00b7hour/BTU", "category": "other", "type": "standard", "teaser": "Express conductive resistance in inch-pound-friendly units.", "labels": {"in1": "Thermal resistance (K/W)", "in2": "\u00b0F\u00b7hour/BTU"}, "factor": 0.5275279263},
+  {"slug": "thermal-resistance-fahrenheit-hour-btu-to-k-per-watt", "name": "Thermal resistance (\u00b0F\u00b7hour/BTU) to K/W", "category": "other", "type": "standard", "teaser": "Go back to SI resistance units from imperial BTU-based values.", "labels": {"in1": "Thermal resistance (\u00b0F\u00b7hour/BTU)", "in2": "K/W"}, "factor": 1.8956342406},
+  {"slug": "thermal-conductivity-w-per-meter-k-to-btu-per-hour-foot-fahrenheit", "name": "Thermal conductivity (W/(m\u00b7K)) to BTU/(hr\u00b7ft\u00b7\u00b0F)", "category": "other", "type": "standard", "teaser": "Swap metric conductivity into BTU-foot systems for insulation tables.", "labels": {"in1": "Thermal conductivity (W/(m\u00b7K))", "in2": "BTU/(hr\u00b7ft\u00b7\u00b0F)"}, "factor": 0.5777893165},
+  {"slug": "thermal-conductivity-btu-per-hour-foot-fahrenheit-to-w-per-meter-k", "name": "Thermal conductivity (BTU/(hr\u00b7ft\u00b7\u00b0F)) to W/(m\u00b7K)", "category": "other", "type": "standard", "teaser": "Return imperial conductivity values to SI.", "labels": {"in1": "Thermal conductivity (BTU/(hr\u00b7ft\u00b7\u00b0F))", "in2": "W/(m\u00b7K)"}, "factor": 1.7313441288},
+  {"slug": "specific-heat-j-per-kg-k-to-cal-per-gram-c", "name": "Specific heat capacity (J/(kg\u00b7K)) to cal/(g\u00b7\u00b0C)", "category": "energy", "type": "standard", "teaser": "Switch joules per kilogram into calories per gram.", "labels": {"in1": "Specific heat capacity (J/(kg\u00b7K))", "in2": "cal/(g\u00b7\u00b0C)"}, "factor": 0.0002390057},
+  {"slug": "specific-heat-cal-per-gram-c-to-j-per-kg-k", "name": "Specific heat capacity (cal/(g\u00b7\u00b0C)) to J/(kg\u00b7K)", "category": "energy", "type": "standard", "teaser": "Express calories per gram as joules per kilogram.", "labels": {"in1": "Specific heat capacity (cal/(g\u00b7\u00b0C))", "in2": "J/(kg\u00b7K)"}, "factor": 4184.0},
+  {"slug": "specific-heat-j-per-kg-k-to-btu-per-pound-f", "name": "Specific heat capacity (J/(kg\u00b7K)) to Btu/(lb\u00b7\u00b0F)", "category": "energy", "type": "standard", "teaser": "Relate SI heat capacity to imperial Btu per pound-degree.", "labels": {"in1": "Specific heat capacity (J/(kg\u00b7K))", "in2": "Btu/(lb\u00b7\u00b0F)"}, "factor": 0.0011608773},
+  {"slug": "specific-heat-btu-per-pound-f-to-j-per-kg-k", "name": "Specific heat capacity (Btu/(lb\u00b7\u00b0F)) to J/(kg\u00b7K)", "category": "energy", "type": "standard", "teaser": "Return imperial values to metric Joule units.", "labels": {"in1": "Specific heat capacity (Btu/(lb\u00b7\u00b0F))", "in2": "J/(kg\u00b7K)"}, "factor": 861.4175127},
+  {"slug": "specific-heat-j-per-kg-k-to-kj-per-kg-k", "name": "Specific heat capacity (J/(kg\u00b7K)) to kJ/(kg\u00b7K)", "category": "energy", "type": "standard", "teaser": "Move the metric values up to kilojoules.", "labels": {"in1": "Specific heat capacity (J/(kg\u00b7K))", "in2": "kJ/(kg\u00b7K)"}, "factor": 0.001},
+  {"slug": "specific-heat-kj-per-kg-k-to-j-per-kg-k", "name": "Specific heat capacity (kJ/(kg\u00b7K)) to J/(kg\u00b7K)", "category": "energy", "type": "standard", "teaser": "Drop kilojoules back to joules.", "labels": {"in1": "Specific heat capacity (kJ/(kg\u00b7K))", "in2": "J/(kg\u00b7K)"}, "factor": 1000.0},
+  {"slug": "volumetric-heat-capacity-j-per-cubic-meter-k-to-btu-per-cubic-foot-f", "name": "Volumetric heat capacity (J/(m\u00b3\u00b7K)) to Btu/(ft\u00b3\u00b7\u00b0F)", "category": "energy", "type": "standard", "teaser": "Convert SI volumetric capacity into familiar English units.", "labels": {"in1": "Volumetric heat capacity (J/(m\u00b3\u00b7K))", "in2": "Btu/(ft\u00b3\u00b7\u00b0F)"}, "factor": 1.49107e-05},
+  {"slug": "volumetric-heat-capacity-btu-per-cubic-foot-f-to-j-per-cubic-meter-k", "name": "Volumetric heat capacity (Btu/(ft\u00b3\u00b7\u00b0F)) to J/(m\u00b3\u00b7K)", "category": "energy", "type": "standard", "teaser": "Return to SI volumetric heat values.", "labels": {"in1": "Volumetric heat capacity (Btu/(ft\u00b3\u00b7\u00b0F))", "in2": "J/(m\u00b3\u00b7K)"}, "factor": 67066.1024763},
+  {"slug": "volumetric-heat-capacity-j-per-cubic-meter-k-to-kj-per-cubic-meter-k", "name": "Volumetric heat capacity (J/(m\u00b3\u00b7K)) to kJ/(m\u00b3\u00b7K)", "category": "energy", "type": "standard", "teaser": "Raise SI volumetric capacity into kilojoule scale.", "labels": {"in1": "Volumetric heat capacity (J/(m\u00b3\u00b7K))", "in2": "kJ/(m\u00b3\u00b7K)"}, "factor": 0.001},
+  {"slug": "volumetric-heat-capacity-kj-per-cubic-meter-k-to-j-per-cubic-meter-k", "name": "Volumetric heat capacity (kJ/(m\u00b3\u00b7K)) to J/(m\u00b3\u00b7K)", "category": "energy", "type": "standard", "teaser": "Shrink kilojoule-based volumetric capacities back into joules.", "labels": {"in1": "Volumetric heat capacity (kJ/(m\u00b3\u00b7K))", "in2": "J/(m\u00b3\u00b7K)"}, "factor": 1000.0},
+  {"slug": "thermal-conductivity-w-per-meter-k-to-cal-per-centimeter-second-c", "name": "Thermal conductivity (W/(m\u00b7K)) to cal/(cm\u00b7s\u00b7\u00b0C)", "category": "other", "type": "standard", "teaser": "Switch metric conductivity into caloric units per centimeter per second.", "labels": {"in1": "Thermal conductivity (W/(m\u00b7K))", "in2": "cal/(cm\u00b7s\u00b7\u00b0C)"}, "factor": 0.0023900574},
+  {"slug": "thermal-conductivity-cal-per-centimeter-second-c-to-w-per-meter-k", "name": "Thermal conductivity (cal/(cm\u00b7s\u00b7\u00b0C)) to W/(m\u00b7K)", "category": "other", "type": "standard", "teaser": "Convert the caloric format back into SI watts per meter per Kelvin.", "labels": {"in1": "Thermal conductivity (cal/(cm\u00b7s\u00b7\u00b0C))", "in2": "W/(m\u00b7K)"}, "factor": 418.4},
+  {"slug": "heat-flux-density-w-per-square-meter-to-btu-per-hour-square-foot", "name": "Heat flux density (W/m\u00b2) to BTU/(hr\u00b7ft\u00b2)", "category": "energy", "type": "standard", "teaser": "Translate metric heat flux onto imperial area units.", "labels": {"in1": "Heat flux density (W/m\u00b2)", "in2": "BTU/(hr\u00b7ft\u00b2)"}, "factor": 0.3169983306},
+  {"slug": "heat-flux-density-btu-per-hour-square-foot-to-w-per-square-meter", "name": "Heat flux density (BTU/(hr\u00b7ft\u00b2)) to W/m\u00b2", "category": "energy", "type": "standard", "teaser": "Turn imperial heat flux back into SI watts per square meter.", "labels": {"in1": "Heat flux density (BTU/(hr\u00b7ft\u00b2))", "in2": "W/m\u00b2"}, "factor": 3.1545907453},
+  {"slug": "heat-flux-density-w-per-square-meter-to-w-per-square-foot", "name": "Heat flux density (W/m\u00b2) to W/ft\u00b2", "category": "energy", "type": "standard", "teaser": "Convert metric heat flux into square-foot units.", "labels": {"in1": "Heat flux density (W/m\u00b2)", "in2": "W/ft\u00b2"}, "factor": 0.09290304},
+  {"slug": "heat-flux-density-w-per-square-foot-to-w-per-square-meter", "name": "Heat flux density (W/ft\u00b2) to W/m\u00b2", "category": "energy", "type": "standard", "teaser": "Translate square-foot flux back into square meters.", "labels": {"in1": "Heat flux density (W/ft\u00b2)", "in2": "W/m\u00b2"}, "factor": 10.763910417},
+  {"slug": "heat-transfer-coefficient-w-per-square-meter-k-to-btu-per-hour-square-foot-f", "name": "Heat transfer coefficient (W/(m\u00b2\u00b7K)) to BTU/(hr\u00b7ft\u00b2\u00b7\u00b0F)", "category": "energy", "type": "standard", "teaser": "Express SI convective coefficients in imperial units.", "labels": {"in1": "Heat transfer coefficient (W/(m\u00b2\u00b7K))", "in2": "BTU/(hr\u00b7ft\u00b2\u00b7\u00b0F)"}, "factor": 0.1761101837},
+  {"slug": "heat-transfer-coefficient-btu-per-hour-square-foot-f-to-w-per-square-meter-k", "name": "Heat transfer coefficient (BTU/(hr\u00b7ft\u00b2\u00b7\u00b0F)) to W/(m\u00b2\u00b7K)", "category": "energy", "type": "standard", "teaser": "Return imperial coefficients back into SI.", "labels": {"in1": "Heat transfer coefficient (BTU/(hr\u00b7ft\u00b2\u00b7\u00b0F))", "in2": "W/(m\u00b2\u00b7K)"}, "factor": 5.6782633415},
+  {"slug": "heat-transfer-coefficient-w-per-square-meter-k-to-w-per-square-foot-f", "name": "Heat transfer coefficient (W/(m\u00b2\u00b7K)) to W/(ft\u00b2\u00b7\u00b0F)", "category": "energy", "type": "standard", "teaser": "Move the conduction coefficient into mixed-area and temperature units.", "labels": {"in1": "Heat transfer coefficient (W/(m\u00b2\u00b7K))", "in2": "W/(ft\u00b2\u00b7\u00b0F)"}, "factor": 0.0516128},
+  {"slug": "heat-transfer-coefficient-w-per-square-foot-f-to-w-per-square-meter-k", "name": "Heat transfer coefficient (W/(ft\u00b2\u00b7\u00b0F)) to W/(m\u00b2\u00b7K)", "category": "energy", "type": "standard", "teaser": "Convert the mixed imperial SI coefficient back into its base units.", "labels": {"in1": "Heat transfer coefficient (W/(ft\u00b2\u00b7\u00b0F))", "in2": "W/(m\u00b2\u00b7K)"}, "factor": 19.3750387506},
 
 ];