Texas Instruments · Algebraic programmable · 1979–1983
The TI-58 of 1977 had one big flaw: switch it off and your program was gone. The TI-58C fixed that in 1979 with Constant Memory, swapping the power-hungry memory chip for a low-power CMOS one so programs and data stay put. Everything else is TI-58: up to 480 program steps or 60 memories, AOS algebraic entry, a red LED display and a slot on the back for Solid State Software modules, with the Master Library in the box. TI sold a dozen more modules for statistics, real estate, surveying, navigation and aviation. Wikipedia notes a TI-58 was used in the Harrier jump jet for stabilization during takeoff and landing. TI replaced it with the TI-66 in 1983.
Good forSurveying and real estateCollecting
Bench check
Should come with it
Check the listing photos against this list, and ask the seller about anything you can’t see. A missing piece should come off the price.
The BP1A pack is usually dead or leaking by now, and a flat pack loses the memory too. Plain TI-58s get listed as 58Cs, so check the badge.
New to old calculators? The condition checklist covers battery corrosion, displays, keys and card readers, and RPN in one hour gets you typing on an HP.
Buying guide
Nothing here is titled working, so we'd only buy a TI-58C as a project, starting with the untested one at $37 delivered. Only 9 are listed, so the $40-85 band shows what untested and as-is units ask, not what a working one costs, and the one sold with a PC-100A printer cradle asks $300. Three of the photos show a badge reading plain TI Programmable 58, which forgets programs at switch-off, so check for the C before anything else. Treat any BP1A pack as dead and never run it on the AC9131 charger without a pack fitted, since TI warns that can damage it, and ask for a photo of the battery bay to check for leak crust. If one powers up, store a number, switch off and on, and recall it to check the Constant Memory.
$37.08est. delivered
Untested at $37 delivered, under the bottom of the band, from a 100% seller. The photo's too small to read the badge, so ask for a close photo showing 58 C and one of the battery bay before you buy.
Texas Instruments TI-58C Calculator UNTESTED
Delivered prices include shipping as eBay quoted it to a US address on Oct 15, 2026. Many sellers charge by distance, so your total may differ. eBay shows yours before you pay.
Snapshot
Checked . Some may have sold.
Delivered prices include shipping as eBay quoted it to a US address on Oct 15, 2026. Many sellers charge by distance, so your total may differ. eBay shows yours before you pay.
For parts$37.08est. delivered
$29.99 + $7.09 shipping
Buy It Now$29.99
Project piece
Untested. The photo's too small to read the badge.
Seller: irolek45
100% positive
For parts$50.53delivered
$50.53 · free shipping
Buy It Now$50.53
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Our take
Sold as is with the Master Library module and no battery. Photo shows a 58 C badge and a case.
Seller: baidil2
99.9% positive
Used$75.00est. delivered
$55.00 + $20.00 shipping
Buy It Now$55.00
Our take
With a module and case, and the photo shows a 58 C badge. No test claim. Ships from Egypt.
Seller: tifsasa-0
99.3% positive
Used$83.02est. delivered
$66.00 + $17.02 shipping
Buy It Now$66.00
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Our take
With the Master Library module and a case. No test claim.
Seller: makin_da_money
99.1% positive
For parts$33.51est. delivered
$25.99 + $7.52 shipping
Buy It Now$25.99
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Check the seller
Untested. The photo badge reads TI Programmable 58, with no C.
Seller: djadi_1929
100% positive
For parts$34.95delivered
$34.95 · free shipping
Buy It Now$34.95
Check the seller
Untested, as is, with a module. Same title as two other sellers, and the photo badge reads 58 with no C.
Seller: jarh-73
99.4% positive
For parts$41.10est. delivered
$30.00 + $11.10 shipping
Buy It Now$30.00
Check the seller
Untested, as is, with a module. Same title as two other sellers, and the photo badge reads 58 with no C.
Seller: clothingandmorestore
100% positive
Used$299.99delivered
$299.99 · free shipping
Buy It Now$299.99
This seller takes offers, and many sellers accept less than the asking price.
Fine if you might miss it? Send an offer first. Someone else can still buy it while you wait for a reply.
Want it for sure? Use Buy It Now.
Priced high
With a PC-100A printer cradle, no key. No test claim, at about 4.8 times the median.
Seller: best-deals-free-shipping
99.1% positive
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